1 Extra Battery... Mugen 3600mah extended battery.. Works great. Just did some travel last week, listened to Music and watched a couple of movies while I was stuck in BWI.. Then watched another movie and finished out the rip with music.. Battery life on the Mugen is amazing... I don't carry any others with me.. Had to get a DS case to fit the extended cover. I actually prefer the extended battery case that the mugen uses.. Easier to hold. Downside, I cannot use the stock car mount.. Oh, well.

I'd love to pick up a nice BP-4L as a spare, along with a good low cost charger. I tried to pick up one already, but that turned out to be the wrong one. Oh well. lol. If anyone needs a charger for an N95, I've got one. ^_^;;

Anywho, a spare battery for my NITs wouldn't be all that bad an idea. Then again, I can just pack my MP1550 along with me and just charge it anytime I have a moment to sit still for a bit.

I've got one that only lasts half as long as it's supposed to. I ordered a new one from ebay, but I received a sidekick shell instead and still have not gotten the battery. Where do you guys buy your batteries? Are the ebay ones high quality? I found bp-5l batteries there for $6-10. I also got a usb charger for $3, works good.

Beware of those ones that are so cheap, you'll usually end up getting what you paid for.

I would recommend only buying from reputable places, NEW, not used. I got mine from PC Connection, although I can't recommend them for speed (my battery was backordered for a month before they even shipped it) I did get a real Nokia battery which is worth the price premium in my opinion.

I also have 2 batteries, since nokia replaced my defective n800 with a brand new unopened box (thus I also have plenty of styli and an extra cloth case). After two years, they're both starting to show their age, though a single battery can still easily make it through a day of heavy mp3 and radio listening and moderate web browsing. Since March 2007, I've yet to have a day when both batteries ran out.

Edit: I'd like to add that when they were new, each of my batteries could watch 2-3 hours of mediastreamer content at medium brightness. Now they are about 1:20-1:40 at low.

2 Nokia batteries, 1 Mugen 1800Mah and 1 fake Nokia I bought with a battery charger on Ebay.

2 cheap no-name spares bought from a company I can't recall (not off ebay), plus the original nokia battery. all still work great ( = up to 2 hours use watching on-tablet video and/or web surfing and/or skype) at least 2 years on; I tend to swap them when/if one runs down, then leave it in place after that as usually I can just recharge - except on plane trips. an external charger sounds handy, but in truth I am able to find time to recharge them all before using up all 3 at once.

I have no spare batteries for my N800, and there's a reason for that: I have spare batteries for other devices, including my main camera (where, due to replacements, I ended up with 3 batteries). Turns out I never use the spares, or at least extremely rarely. The only thing I get out of spare batteries is the knowledge that they are just now sitting in storage, slowly degrading as all lithium batteries do.

The battery I have in my N800 now is more than two years old and it's not as good as it was, so when I find a battery fresh from the factory (trying to avoid those with a long shelf-life behind them already), I'm not going to keep the old one as "spare": I'll give it to the shop instead (or another place where they accept stuff that can't be thrown in the garbage).

Wait a second. I didn't think the BP-5L was designed to work in the tablets. If it is, or it's compatible, what's the advantage of it?

In my experience, cheap is just fine. I have a couple of slightly higher capacity batteries and I only use them now. They are very nice and I don't remember where I got them, but not ebay, which I am permanently boycotting. Just google and you will find similar deals.

I use a cheap charger I bought from ebay a couple of years ago.

I don't have spares for my N810.

It appears to me that when you buy cheap Hong Kong batteries, you are getting good quality batteries, as a rule. No one has reported their tablet damaged by a battery here, ever