Batteries come in all kinds of qualities and cycle ratings. Lead acid batteries (still really common) also have cycle curves that are based heavily on temperature and DoD (depth of discharge) - most offgrid set ups are trying to keep worst case DoD below 20-30% (aka SoC 70-80%) to keep total cycles up above 3000. There's usually a nice knee in the curve there: http://www.rpc.com.au/pdf/rayl... (page 11).

The LFP/LiFePO4 lithium batteries that are gaining in popularity achieve that kind of cycle life but with DoD around 70-80% (again, less DoD = more cycles).

There's also Nickel Iron batteries (https://en.wikipedia.org/wiki/Nickel%E2%80%93iron_battery) - hard to buy new at the moment because they fell out of favour (heavy per Wh) but known to last more than 50 years with no cycle memory - some manufacturers starting to build them again for this kind of application (i.e static applications where weight doesn't matter).

You can pay much more or less than $800/kWh depending on quality and what kind of DoD you're going to run (i.e how long you want your batteries to last).

400A!?!?!? Surely you mean 40A?

Surely given their past history you'd expect that this technology actually came from a "better" company :)

Remember the milk has been doing this for a while:
http://blog.rememberthemilk.com/2009/09/new-for-pro-remember-the-milk-for-android/

Have you got anything at all to back up this statement?

The Kindle 2 and 3 do have different slot spacings. The devices themselves are actually different sizes despite having the same size screens. You can't put a leather case from a Kindle 2 on a Kindle 3 anyway.

The above is based on observations I've made on the Kindle 2 & 3 + matching leather cases that my partner and I have.

I'm guessing someone somewhere had actually though through making them physically different for this reason, but when it came to manufacturing them that little gem of an idea got lost somewhere.

Serious question...

Did you have to do anything special to get tags to work?

Are you only using Thunderbird or other clients as well?

Does it support unlimited tags?

350ppm isn't arbitrary it's the maximum safe amount of CO2 we can stabilise at in the atmosphere to ensure we don't experience catastrophic global warming. http://arxiv.org/abs/0804.1126

Do you need to accurately quantify it?

We're all pretty well aware CO2 is too concentrated in the atmosphere already, and we should be aiming to get back under 350ppm (see http://www.350.org/mission for a _really_ brief overview).

Why not just aim a tax roughly at getting back to 350ppm?

Just run two. Only one of them has to have real world data, the other one siphens IPs to your firewall software :)