Nothing. If you want something for your invites, go to gmailswap or ebay. Otherwise give them out. You'll get bored of getting them though, I've given away about 30 in the last two weeks.
Uh, I guess I want one. If there are any invites left, and I haven't made you hate me yet, kick an invite to agile_one@hotmail.com and I'd be mucho appreciative.
I have 3 more invites. Anyone who wants in can just PM me, I'll give 'em to the first 3 PMs. Since my friends all seem to want to keep their uni addresses and don't care about gmail, this is a once-in-a-lifetime-opportunity.