Default Does anyone have any tips to improve battery life without reducing perforrmance?

I have an official 1.66.405.2 ROM with radio 2.06.51.07. Initially I used to get about 1.5 days battery life with moderate use. I then installed some opera tweaks which has improved performance but now battery life is getting to 1 day or under. Anyone have any tweaks/tips or cabs to improve battery life without reducing performance. For example do you recommend a particular radio or should I alter data disconnection. I have tried disabling all data connections by holding the R softkey which does help.