Topic: WARNING: Some microSD cards can 'brick' if power's cut @ a bad time
I upgraded from a 1GB to 8GB microSD card (Sandisk class 2, $20 at rat shack) and set it up to do background mic recording. This worked great until the power got bumped out and the card corrupted itself and can't even be accessed in a USB reader under Linux. Hopefully I can fix that by formatting it in a digicam.
Moral of the story? When using a cheap microSD card, always have a battery (mine's coming in tomorrow).
Also this could be the cause of some user's black screens, assuming there was a write going on at Exactly The Wrong Time.