Dropbox just doubled up its referral program which means more free storage for you. If you're a free user, you get 500MB of storage space for each Dropbox referral, with a maximum of 32 referrals for 16GB of space.
For Pro users, you'll get 1GB for each referral with a 32GB maximum. This new program works even if you've already invited people to Dropbox which means you'll get the extra space bonus (250MB per referral) for all those lovely folks too. More cloud storage for everyone! [Dropbox via Engadget]