We've all experienced it. A cell phone starts ringing or vibrating. To be clever, it slowly starts getting louder in case the owner didn't hear or feel the initial signal. You see somebody going through their bag looking for the phone that keeps getting louder and louder. Finally they answer and it shuts up.

My prior post about USB charging hubs in hotel rooms brought up the issue of security, as was the case for my hope for a world with bluetooth keyboards scattered around.

Is it possible to design our computers to let them connect to untrusted devices? Clearly to a degree, in that an ethernet connection is generally always untrusted. But USB was designed to be fully trusted, and that limits it.

What should be in a good hotel room?

Well, one thing that's easy to add to the list is a powered USB hub, with as many as 6 ports and a 3 amp power supply. Toss in some mini-USB cables (possibly just built into the hub) as they have become, for better or worse, the present-day universal charging standard. (At only 2.5 watts, USB is a bit anemic as charging standard, but it's what we have for now.) A mouse would be nice too, but is a security risk.

Alas, we can't have a keyboard on it, as nice as that would be, since that can't be trusted. It might have a keylogger put in it (even by the previous occupant of the room) to grab passwords.

Now this is a fairly cheap item (under $20) and like many other hotel items, it could also be available at the front desk, though it's so cheap I don't see a reason for that. While you could not be sure it would be there at every hotel, it would still be useful, since it can add to the charging you bring, and most laptops can be a charging station if you are willing to leave them on overnight. It's also useful as a hub. Indeed, have two, one on the desk, and one by the bed for cell phones.

We're almost ready to not need the hotel phone unless you are coming from overseas and pay ridiculous roaming charges. But they still need it to call you sometimes, and I don't want to have to hand over my mobile number at check-in.

Most hotel rooms now are getting a flat-screen HDTV. That's great, but rarely do they offer up the VGA port that many of these TVs have, or a cable to plug it in. I recommend a 1080p TV for each room, located in such a way that it can be an external monitor for my laptop. As such there should be a VGA cable connected or handy. The TV could also be connected to the USB hub, and use a video over USB protocol for devices that have USB out but not video out. (This usually needs a driver and has some limitations.)

Lots of people are doing it -- using their digital camera as a quick way to copy documents, not just for taking home, but to carry around. Rather than carry around a large travel guidebook (where most of the weight is devoted to hotels and restaurants in other towns) we normally just photograph the relevant pages for the area we will be exploring. We also do it even with portable items like guides and travel maps since we don't really want the paper. We also find ourselves regularly photographing maps of cities, facilities and transit systems found on walls.

I'm on the shores of Kinneret (Sea of Galilee to Christians) for Israel's version of FOO Camp. A great time so far, after visiting Haifa and the area. To Tel Aviv on Sunday to speak at the Marker's internet conference for those of you who are in the area.

The news of the past few days has been full of anger that AIG is paying $165 million in bonuses out to managers who drove the company into insolvency, using federal bailout money to do it. The excuse -- these bonuses were guaranteed in contracts.

Last week I wrote about what I consider the main goal of green electricity efforts, namely to stop burning coal. You can do that, to some extent, by removing demand from the grid in places where the grid is coal-heavy. Even in other places, removing demand from the grid will be fairly effective at reducing the production of greenhouse gases.

Update: Since this article a flood of cheap solar panels from China has been changing some of the economics discussed here. I have not altered the article but some of its conclusions deserve adjustment.

No matter what you do -- conserve, or put up solar or wind -- your goal is to take power off the grid. Many people however, consciously or unconsciously take a different goal -- they want to feel that they are doing the green thing. They want their electricity to be clean. This is actually a dangerous idea, I believe. Electrons are electrons. In terms of reducing emissions, you get the exact same result if you put a solar panel on your house than if you put it on your neighbour's house. You even get a better result if you put it on a house that's powered by a coal plant, so long as you also reap the benefit (in dollars) of the electricity it makes.

People don't like to accept this, but it's much better to put a wind turbine somewhere windy than on your own house. Much better to put a solar panel somewhere sunny than on your own house. And much better in all cases if the power you offset is generated by more by coal than at your house.

However, the real consequences are much deeper. The following numbers reveal it is generally a bad idea to put up solar panels at all, at least right now. That's because, as you will see below, solar panels are a terrible way to spend money and time to make greener electricity. Absolutely dreadful. Their only attribute is making you feel good because they are on your roof. But you should not feel good, because you could (in theory, and I believe with not much work in practice) have made the planet much greener by using the money you spent on the panels in other ways.

The true goal is to find the method that provides the most bang per buck in removing load from the dirty grid.

Keep reading to see the math and a spreadsheet with some very surprising numbers about what techniques do that the best.

As you may know, I allow anonymous comments on this blog. Generally, when a blog is small, you don't want to do too much to discourage participation. Making people sign up for an account (particularly with email verification) is too much of a barrier when your comment volume is small. You can't allow raw posting these days because of spammers -- you need some sort of captcha or other proof-of-humanity -- but in most cases moderate readership sites can allow fairly easy participation.

Coach is cramped, but not everybody can afford business class. In addition, there are airlines that require fat people to purchase a second seat if they can't fit into one. Fortunately I am not in that department, but it seems there is an interesting alternative that might make sense for all -- selling half of a middle seat, for half price (or less) to somebody wanting more room in coach.

I recently attended the eComm conference on new telephony. Two notes in presentations caught my attention, though they were mostly side notes. In one case, the presenter talked about the benefits of having RFID tags in everything.

"Your refrigerator," he said, "could read the RFID and know if your milk was expired." In the old days we just looked at the date or smelled it.

I'm looking at you Ubuntu.

For some time now, the standard form for distributing a free OS (ie. Linux, *BSD) has been as a CD-ROM or DVD ISO file. You burn it to a CD, and you can boot and install from that, and also use the disk as a live CD.

There are a variety of pages with instructions on how to convert such an ISO into a bootable flash drive, and scripts and programs for linux and even for windows -- for those installing linux on a windows box.

There are many ways to go green, though as I have identified, the vast bulk of the problem is in just a few areas -- personal transportation, electrical generation, building design/heating/cooling and agriculture.

While those who focus on CO2 work from the fact that both Natural Gas and Coal, which produce 70% of the USA's electricity, emit CO2, coal is a much bigger villain.

There are many opinions about whether the bailout and stimulus package are a good idea or not. But one thing that I hope everybody agrees is bad is that it teaches the lesson that if you screw up so badly that you hurt the global economy, we're not going to let you fall. Take huge risks because in the event of catastrophe, the government has no choice but to make it better.

Is there a way to do a bailout that doesn't end up rewarding, or even saving, the people responsible?

Product recalls have been around for a while. You get a notice in the mail. You either go into a dealer at some point, any point, for service, or you swap the product via the mail. Nicer recalls mail you a new product first and then you send in the old one, or sign a form saying you destroyed it. All well and good. Some recalls are done as "hidden warranties." They are never announced, but if you go into the dealer with a problem they just fix it for free, long after the regular warranty, or fix it while working on something else.

Just returned from BIL, an unconference which has, for the last two years, taken place opposite TED, the very expensive, very exclusive conference that you probably read a lot about this week. BIL, like many unconferences is free, and self-organized. Speakers volunteer, often proposing talks right at the conference. Everybody is expected to pitch in.

I've been very excited with this movement since I attended the first open unconference, known as barCamp. The first barcamp in Palo Alto was a reaction to an invite-only free unconference known as FooCamp, which I had also attended but was not attending that year. That first camp was a great success, with a fun conference coming together in days, with sponsors buying food and offering space. The second barcamp, in DC, was a complete failure, but the movement caught on and it seems there is a barcamp somewhere in the world every week.

This year BIL was bigger, and tried some new approaches. In particular, a social networking site was used to sign up, where people could propose talks and then vote for the ones they liked. While it is not as ad-hoc as the originals, with the board created at the start of the conference, I like this method a lot. The array of sessions at a completely ad-hoc conference can be very uneven in quality, and assignment to rooms is up to a chaotic procedure that may put an unpopular talk in a big room while a small room is packed to the gills. (This even happens at fully curated conferences.)

Pre-voting allowed better allocation of rooms, and in theory better scheduling to avoid conflicts (ie. noting that people want to go to two talks and not setting them against one another.) BIL also had some spare slots for people who just showed up with a talk, to keep that original flavour.

Recently, some prosecutors, in efforts to crack down on drunk driving, are pushing for murder convictions. This is happening in the case of really blatant disregard on the part of the drunk drivers -- people with multiple DUIs getting smashed, going out, and killing.

Here's a short new robocar essay, on Robocars helping bring about flying cars.

The thesis of the essay is simple. The quest for flying cars has always had to deal with the very difficult compromise between a vehicle that flies and one that drives. It's just really hard to make one vehicle to do both.

As I move to get more paper out of my life, one thing I'm throwing away with more confidence is manuals. It's pretty frequent that I can do a search for product model numbers or other things on a manual, and find a place to download the PDF. Then I can toss the manual. I need to download the PDF, because the company might die and their web site might go away.

Here's a nice story about the Kiva warehouse delivery robot now being used by major retailers like The Gap. Factory floor robots have been around for some time, and the field even has a name "automated vehicle guidance systems" but these newer deliverbots kick it up a notch, picking up shelves and bringing them to a central area for distribution, finding their way on their own with sensors.

Since I do so many of my own, you won't find me blogging about other people's panoramas very much but this gigapixel shot of the crowd as Obama gives his inaugural speech is well worth exploring full screen. David Bergman's story of the photo is available.