I'm considering getting this, however I can't seem to find how many mah the standard n800 battery is, can someone give me a comparison, or even better if someone has purchased this, how much continuous use do they get from this. Listening to .ogg files in off-line mode with occasional pop-in's for e-mail and such tto on-line mode gets me about 8 hours on default battery, but I die out on the drive home... I'd love a battery that could get a day or two when I'm on the road.

I believe you can find the mAh on the battery itself, printed on it somewhere.

1500 mah...stock

hmm looked all over mine but didn't see it... thanks though

so it sounds like this will only gain me about an extra hour of run time huh? I guess I can always switch between the stock and 1800 mah but what a pain... oh well

You can also use an external battery, at least according to this page:
http://tabletblog.com/2007/11/review...b-charger.html
So if both the internal battery is charged and the external battery is charged he is saying you get about 3500mah (9 hours) of time.

You might be able to use these batteries also and they charge either through AC or sun light, the first one is 2800mah and the second is 1250mah :
http://www.amazon.com/Foldable-solar...1645493&sr=8-5
http://www.amazon.com/Solar-battery-...1645493&sr=8-1

I've seen some other strange charging devices, such as having a charger that is attached to a bicycle, so you can charge your cell phone or mp3 player when you ride your bike.

In looking at it further I think these external batteries give you the most bang per buck (or in this case mAh per USD)

http://www.amazon.com/Digipower-EBP-...1664320&sr=8-6

http://www.amazon.com/gp/product/B00...449CXHAJD5FB6A

The black and decker one looks kinda big, but it provides an AC outlet so you can plug in the AC adapter into it directly instead of having to do the USB adapter charging trick in tablet blog link. I'm thinking of getting it for my laptop, just don't know how big it is exactly :P.

I have 2 of the black and decker power packs, and they are about 1/2 an inch bigger around my N800 when I sit it roughly in the middle of the pack and easily twice as thick. It's about an inch bigger around my N810. I bought these two from woot a little while back for 20$ shipped. While they are physically big, they are fairly light and can charge the tablet several times before needing to plug them in. They don't come with a car charger, so you have to make sure you've charged them up fully before going on that plane trip or what have you. I wouldn't carry them around for use daily, but if you are going to be away from a power source for an extended period, they come in handy!

Anyone have any experience with the mugen batteries for the n810? I just got the 1800mAh and it doesn't seem to work at all. It says on the package to charge for 12 hours before use but the battery shows no signs of charging and I hear a clicking sound coming from my NIT.

Must be a defective battery. I charged mine originally for the required 12 hours and have now been using it for a month without any issues. I thought I was going to get more battery time out of it than the standard battery, but i'm not getting any less; 10 days standby / 7 hours of use. $30.00 and that included shipping wasn't a bad price.

Sounds like you've received a bad one.