Are you familiar with the Timeriffic app (http://www.appbrain....fray.timeriffic
)? It allows you to create profiles that control settings on a schedule. For instance, I use a work week profile that puts my HTC Evo into airplane mode during the times I'm commuting to/from work on our subway system with no connection. Once I get to work, it takes my phone out of airplane mode, with GPS and WiFi turned off, and uses my cube-farm friendly volume settings. It mutes my phone automatically during my daily status meeting, then automatically un-mutes at the end of the half-hour. Once I'm home, it reactivates WiFi and turns up all the volume settings -- until bedtime.
This helps manage battery life without my having to remember to manually make these adjustment.
And then, I could set up a vacation profile...