Bioshock 2 retail physical copy for $2.00 here: http://www.inetvideo.com/products/biosh…
Since this game switched to steamworks from GFWL, retail keys activate on Steam with minervas den DLC included.

Everyone gets those games when they create a gog account. They are always free.
And they don't send actual codes, they just make the games accessible from your account so you can't give them away per se.