The idea of selling EV battery energy back to the grid is silly given the high depreciation costs of current EV batteries, but a closely related idea makes a lot of sense: allowing the grid operators to control the power level of EV chargers in exchange for lower rates. Even during the day there's almost always unused generation that's much cheaper than the depreciation cost of EV batteries. Problem is, it takes time to fire up in response to an unexpected load increase. Usually the extra load is temporarily met with quickly dispatched (but more costly) spinning reserves until the more economical generators are online. Temporarily reducing EV charging powers could be an alternative to those expensive reserves, and it only needs to last until the extra generation is online. The temporary power reductions could be rotated among different EV drivers so no one user has his cranked down too often or for long.

Last night I was running Skype on a publicly routable IP address, which probably made my machine a supernode candidate. I noticed a lot of idle traffic between my Skype client and quite a few IP addresses within the Amazon EC2 compute cloud. I'd never seen that before. Usually my background traffic is to random cable and DSL addresses. My guess is that Amazon is where Skype brought up their "extra mega-supernodes". EC2 is handy for things like that.

I'm a big Mac and OSX fan. OSX is a good UNIX system that also makes a good development front end for Linux and BSD. But I have absolutely no interest in developing or even owning an iPhone. First, it doesn't work with CDMA networks like Verizon and Sprint. Second, it's not really your phone if you have to get Apple's permission to run a program on it. People really should avoid locked-down platforms like the iPhone. They're simply not worth it. Buy a small netbook instead.

You're exactly right, Zn-air batteries have been around for a long time. Larger Zn-air batteries have also been under development for some time. So it REALLY bugs me when I see a Slashdot title like this one that's just flat-out wrong. Any battery's theoretical energy/weight ratio is determined by its reactants. Not only do you want a lot of energy from each atom or molecule in the reaction, you also want a high ratio of valence number to atomic weight. The nuclei in the reactants are just dead weight to balance the charge on the electrons that do the work. The ideal reactant would be cheap, nontoxic, easy to handle and electrically conductive. Nothing fits them all so you have to compromise. Good battery fuels are easier to find than good battery oxidizers. You can't beat lithium as a fuel if you want a metal at standard temperature and pressure. The oxidizer is the big problem. In current use are MnO2, LnxCoO2, LiFePO4, AgO, PbO2, NiOOH, SO2, SOCl2, SO2Cl2, FeS, CF(n), HgO, S and lots and lots of others. They're all heavy, expensive, toxic, and/or non-conductive. So using O2 from the air as an oxidizer is a really big win if you can do it. Zinc-air batteries and automotive fuel cells already do this. (Fuel cells for space use have to carry both H2 and O2.) So it seems to me that if you can make a rechargeable battery with Li as the fuel and atmospheric O2 as the oxidizer, you'd really have something.

So this asks the obvious question: is Skype still secure?

Obviously it can be broken by planting malware in the target's computer, but what are the other ways? Last we heard, independent reviews of the crypto protocols said they were pretty good.

But I am quite sure there are exploitable weaknesses in the login server and protocol. Skype operates that server, so we can assume that it either is or soon will be compromised.

Consider the following simple observations. I can install Skype on another computer, sign in with my existing user name and password, and talk to any of my existing contacts without any of them noticing anything unusual. I transferred nothing from my old installation, so my new installation cannot have any of its existing secrets. It knows only one long term secret: my account password, and I use that only to authenticate myself to the Skype login server.

Furthermore, unlike most IM programs, I can sign in from multiple computers and switch between them during chat sessions. All will get copies of all that is said.

This seems to demonstrate quite clearly that with the cooperation of the operator of the Skype login server, you can impersonate any Skype user and conduct either a man-in-the-middle attack or a conferencing attack.

The weakness here is that you're relying on the login server to authenticate your correspondents instead of doing it yourself on an end-to-end basis. Without authentication, encryption is meaningless.

You could probably add packet-level authentication mechanisms to Skype traffic to protect against this attack, but if you're going that far you might as well use something completely different that you can fully trust.