I've noticed that battery life is a common conversation topic on these forums, so I figured it would be nice to aggregate all of that into one thread. You can post the amount of battery life you can get using different combinations.
My most recent battery discharge lasted 24 hours with minimal usage, but that included a 30 minute GPS run with RunKeeper. I'm using P3Droid's 250-1100mhz kernel. I am using SetCPU on interactive with a 250mhz minimum when the screen is off.
One thing to remember though, most of the battery is drained by the display and not the CPU. Go into Settings > About phone > Battery usage and you will see what I mean. The longer your display is on, the less life it will have.