funny story - could have sucked:
I've been playing with my phone, making changes with htc home, etc. I accidently set the backlighting control to one of my quick launch buttons - which i then clicked a couple of times by accident. Everything went dark, and i couldn't figure out how to brighten the screen. I fiddled with it for a 30 minutes trying to remember how to (and where to push) to adjust the lighting. I was getting worried that i was going to have to hard reset it (after just getting everything the way i wanted it). I managed to brighten the screen, so disaster averted. Also noticed that i had deleted some things while playing with it darkened.
Anyway, close call that was very annoying. I'll try not to do that again