Spore and all it's addons are available on Steam for 75% off. $4.99 for the base game, $9.99 for the base game and one of two addon options, or 14.99 for the game and both addon options.
Pretty sure it still requires EA/Origin logins to play. And if you go by the Steam forums for the game, apparently enough people are buying it on sale and trying to log in to play that it's causing log in errors and such.
Also, in case by some stroke of luck you don't have Portal or Portal 2, both are on sale this weekend, 75% off. 4.99 for Portal 2, 2.49 for Portal 1, or 6.24 for both.
Edited, Apr 18th 2013 8:11pm by TirithRR
Can't sleep, clown will eat me.