fyi, the vibe doesn't actually take much power at all. It's the push connection/waking up and talking to email servers that is the biggie here.

Owning both ends of the link (as blackberry do) is about the only way to really get push mail working in a lean fashion. WinMo and exchange activesync suffer pretty much the same as the iPhone does with push...

As I just said, bluetooth is a real power miser. I've never turned it off myself. WiFi, even if associated to a network, is very low power. 2G, as the settings menu says, takes less power than 3G, especially for sparse data traffic.