Mine syncs my documents, pictures, music with my desktop, iphone and laptop. I never have to worry about emailing myself files, transfering via USB, etc.
1) Use Dropbox Portable to open Dropbox files on public computer
2) Sync passwords with Keepass
3) View files on your iphone
4) Start bittorrent downloads anywhere
5) Sync firefox profiles including settings, bookmarks, etc. across multiple computers
6) Sync iTunes library (note may need more storage)
7) Share folders with friends (i.e. pictures, documents, etc.)
8) Host a website on your dropbox
9) Sync Windows saved games across computers.
10) Have more than one account. Learn how to run multiple dropbox accounts at the same time.
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