[artmageddon]

I use it for both, but mostly sharing. Dropbox starts you off with 2GB but allows you to increase the size for free by referring other people, which I've been able to do. I've gotten it up to 8GB thus far. I don't rely on it to keep all of my most important data, since that goes well beyond 8GB, and I don't keep anything personally sensitive on there either. If my friends need something like pictures I've taken at a party, I'll put them on Dropbox and let them deal with it, rather than the hassle of email or setting up my own server.

While it's limiting, I like it a lot better than carrying USB sticks with me - I've lost a number of them over the when they'd eventually rip off my keychain :(