It's guaranteed that anyone working in I.T. will have a couple of USB sticks in their pocket and if you leave them open-ended it's guaranteed the dust bunnies will nest in there. I got fed up of removing the pocket fluff so have designed a simple clip and protector for my Cruzer USB sticks

The centre post is slightly flared at the top so push the memory stick on hard and it will stay in place. The action will be stiff at first but work it a bit and it will free up. A tiny drop of liquid soap works wonders too. Print in different colours so you know which stick is which.
The end is slightly sprung to keep the stick in place when closed.