Dropbox is currently running a promotion where you can get an extra free 1GB added to your account by doing a sort of treasure/scavenger hunt with riddles and whatnot. Didn't take long with the cheat page, and gave me an extra gig, which is always nice. Links below!
Sign up for Dropbox
Start Dropquest (to earn extra 1GB)
Dropquest 2011 Cheat Page
Sign up for Dropbox
Start Dropquest (to earn extra 1GB)
Dropquest 2011 Cheat Page