My Co-op has to deal with the british equivalent of Wal-Mart bikes, as word seems to have gotten round that we're the only place that will touch the damn things. I'd estimate a quarter of them have cranks that have fallen off.

Also, we had one yesterday that said "A new dawn in mountain biking" on the seatstays. Gas-pipe clunker, dual suspension, probably weighed as much as I do, but it had that written on it.