I like using Dropbox
for several reasons: quick, convenient, light, and... pretty. 2GB free and a good iPhone app etc etc.
have a referral scheme: invite someone & you get an extra 250mb of storage space free for life. In my time with them I've only had a few referrals.
Next up is google adwords. Now, for a while I keep having google e-mail me with £75 free advertising (I know Fwetch has too, he even got a physical letter!) but have ignored it as... well, what will I advertise?
Last night I got another e-mail from google whilst I was on dropbox and thought - I'll advertise my dropbox referral link!
I made an add for Dropbox - no one would know it wasn't official; to the point, listed dropbox.com as the url (but of course it actually went through my referral link) and they'd never know. In fact, they got an extra 250mb out of it as well (you get that if you sign up using someones referral link).
I used the obvious searches: free storage, online storage etc etc.
Within 5 hours I'd had 50 people sign up for dropbox thus maxing me out on referrals... So I woke up with 50 e-mails from dropbox saying they were adding another 250mb! (until I reached the cap of extra 8GB)
Anyway, just wanted to share my genius so you could awe over it &, if fwetch or anyone still has an adwords voucher, do the same for anything else they have a referral link for! (I thought of clanservers (yes, this doesn't affect us anymore :P ) and rapidshare (wouldn't be comfortable advertising them...))