My n900:

Titans power kernel with limits set to 250 and 900. almost all apps from extraswith a few from testing. facebook and skype are always on, almost always using wifi, if not then 2-2.5g only. screen brightness at 2/5 bars. always on silent mode, but do have haptic feedback on for touchscreen... I text, skype, browse web, and listen to music throughout the day...

My phone will last about 3.5-7 hours. I almost always plug it into usb to charge while at home, and between classes during the day at school.

got some suggestion. Why not try to put in one of these in your n900? I can assure you great battery life.

our n900s are pretty much turning into nuclear submarines...

There is a fix for Hildon from MohammedAG, that really improves stand-by battery life. Can't find the site again though.

Paai

Just to share my battery life result:

I started using my N900 about 3 months ago, current battery life still approx 1day to 1.5days. WIFI is on 24hrs, 3G, average call usage, music and general tweaking around some applications. I don't save on applications and widgets (what's the point of having this great phone when you need to skim on the cool features, right?). I'm not familiar with tweaking the kernel stuffs (though I wish I did) so it's original settings mainly.

But I sure wished the N900 battery could last longer. My 2yrs+ Blackberry Curve 8320 lasts up to 3-4days (with 24hr WIFI, emails and min phone usage)

Generally my N900 dies in 1.5days, but if I push it haaaard, it dies in 6 odd hours.

Everyone with bad battery should try to learn about PowerTop. It is not easy understanable.. but very good. Also Top -> "p-key" or "m-key" to see processes and memmory usage is good.

I have about 3 days usage on one charge... if i don't go 1.15ghz and see video or something heavy. Just normal use. I am constantly using wifi or 3g.

Just want to share my experience about the battery. I think the problem is the nokia original charger not the battery. When i recharged my n900 with proporta usb turbo charger 3400, the battery lasted longer compared to when i use nokia charger. Weird, i don't know why. However, the charging time takes longer using proporta.

Hi my N900
last 4-6h if used as a PC and 2-3 days if used as phone.

I am happy with it.

I am online only if needet (auto disconnect) and i have switched off the atomatic indexing.

I'm thinking of getting a second battery, or that Nokia extra power thingy. I believe should come in handy.