Even though I saw the episode of Mythbusters that blew the 3 second rule out of the water, I still let the kids eat stuff they've dropped here at my place. But I try not to let them eat stuff they've dropped at the shops, Doctors, cafes, parks etc. I'm especially anal about shopping trollies - apparently they're one of the worst offenders when it comes to growing and spreading bacteria (I really DO have to stop watching Mythbusters....)