Green Man Gaming has a bunch of SEGA games on sale and if you buy any of them you'll get Jet Set Radio for free! (http://www.greenmangaming.com/ifd-sega/)
So for example, you could get Alpha Protocol and Jet Set Radio, two great games, for only $3.74! Or maybe you're better off buying Sonic Racing Transformed for $4.99 which you could use to play with us. (http://soniczone.net/forum/index.php?topic=35991)
But wait, there's more! If you connect your Steam account to GMG, you'll get a 25% off voucher for an even greater deal! (https://freegame.greenmangaming.com/) You can only use the voucher if you checkout with items that total more than $10 though.
Most (if not all) games are redeemed on Steam. Buy something before the sale ends!
Sorry but I already own all the things I want from the sale.