1. Bought these batteries on ebay. They seem to last much, much longer than the stock battery. HTC EVO 4G SPRINT HERO 2x1800 mAh Battery+Dock USB CHGR - eBay (item 320566818360 end time Aug-01-10 15:38:22 PDT) 2. Installed advanced task manager. I know some people are against task management, but I have found this program doesn't cause my phone to act crazy at all, and saves battery life. Even without running ATM, these above batteries still give me almost double the stock battery.