I'm running out of options besides replacing the battery or getting a new n900 which is just about impossible right now. Here is my setup..

Off the charger at 6 a.m. fully charged
Brand new SIM card
GPS completely off
Bluetooth completely off
Network mode set to GSM
Screen brightness set on lowest
Backlight timeout set to 30 seconds
Always connected to T-Mobile. Wifi set to manual, search interval set to never. Not connected to wifi at all during the day
2 desktops: 1 with facebook, calendar, media player widgets and 2 contact shortcuts. The other with nothing but shortcuts and 2 bookmarks
2 email accounts set to poll every 30 minutes
Mail 4 Exchange set to manually synchronize contacts, calendar

Usually web browsing on EDGE for a total of 1.5 hours
Maybe play 30 minutes of media

Dead by 4 p.m.

I've reflashed more than once and ran with no extras-devel apps with marginal improvement

My signal strength isnt great but I should be getting better battery life even with idle. I've pretty much scaled back the intended use of the n900. Even with light use I have yet to break more than 12 hours on a full charge.

Also, how accurate is the battery information from running "lshal | grep battery"? This morning after coming off the charger and only installing 3 updates, my battery looks full, but my percentage says 86%.

Anymore tips would be greatly appreciated.

Thanks