Screwy Stuff in Space

The recent stories about the repair of the Hubble telescope have been interesting. It sounds like they are doing the equivalent of basic home repairs, only way up in space, which greatly increases the complexity. One thing I've noticed is the large number of screws they have to remove. When I'm doing a project at home, I worry about what to do with all the screws, to make sure I don't lose one. But what do you do with 111 screws up in space?