Yes, there's only a handful of them, you can even make your own .reg file to do it.

I personally haven't noticed much of a difference with them, but eh, I'll take every little bit.

Another thing to consider, if you're on Sprint, re-flash your radio to the Telus/VZW version, this seems to have a HUGE effect on battery life (from my own observations, reduces the drain from a constant 8%/hr to less than 1%/hr to 2%/hr idle).