I've been doing a lot of messing around with underwater photography recently and am starting to run into issues with the closed architecture of the camera system I'm using. One option would be to put a camera in a waterproof housing and use that instead of the purpose built underwater camera I have now. Problem is, my amusing will be homemade and may not be as waterproof as I might like. I'm going to get one or more cheap webcams at the thrift store to experiment with and I totally don't care if they get destroyed. However, if, in the process of their destruction they short out the computer they are attached to, that could be problematic. So, the question is, can a USB device shorting out damage the computer it's attached to, and if so, will putting a USB hub in between protect the computer?