Dropbox likes giving free space to students. On top of already offering extra free space for referrals from student email addresses, you can now get an extra 3GB for two years simply by verifying a university or other education email address.
Dropbox offers the extra space when you verify your .edu.au (or .edu) email address on its Space Race site. Note that you only get the extra storage if at least 25 students are participating from your institution, so talking friends into signing up is worthwhile (and could score you more referral bonuses). Institutions also earn 'points' for each participating student and for these students completing Dropbox's 'Getting Started' guide, with points totals potentially resulting in additional storage space increases. Definitely worth doing if you're eligible.