Ouch. Still, not as bad as the guy (Walt Mossberg, I think?) who chucked out his MBA with a stack of old papers and magazines!!
I remember that and thought of immediately the first (and last!) time I set my iPad on a stack of papers. It would be pretty easy to lose because it's so flat, especially if you live with someone else who might not be as aware of it as you are.
My sister is a flight attendant and she HIGHLY recommends travelers use a brightly colored case, even if it might not be your first choice because you are much more likely to notice it. It also helps them see left items, like phones, etc., when they do their walk-through.