Something weird happened to my Nexus One tonight. I had the phone plugged into USB while at work, and when I went home the battery was full. I left it in my pocket the whole evening (maybe 3-4 hours), but when I got it from the pocket, the phone was off and the battery was completely drained. No calls, no messages. And the phone hadn't been touched. 3G and wifi are enabled, but the phone has always had 15-25% battery left after heavy usage over the day. Am I in the battery twilight zone?