Peggle and Peggle Nights $9.98 or $19.98 for both
(Currently on sale $9.98 for both)
http://store.steampowered.com/sub/1481/ Package
http://store.steampowered.com/app/3480/ Deluxe
http://store.steampowered.com/app/3540/ Nights
Braid $14.99
http://store.steampowered.com/app/26800/
Orange Box $29.99
http://store.steampowered.com/sub/469/
Garry's Mod $10
http://store.steampowered.com/app/4000/
Counter-Strike: Source $19.99
http://store.steampowered.com/app/240/
Bioshock $19.99
http://store.steampowered.com/agecheck/app/7670/
Unreal Tournament 3 Black $19.99
http://store.steampowered.com/app/13210/
Mass Effect $19.99
http://store.steampowered.com/app/17460/
DiRT $19.99
http://store.steampowered.com/app/11440/
Red Alert 3 $29.99
http://store.steampowered.com/app/17480/
Defense Grid: The Awakening $19.99
http://store.steampowered.com/app/18500/
Audiosurf $9.99
http://store.steampowered.com/app/12900/
World in Conflict $29.99
http://store.steampowered.com/app/21760/
Crysis and Crysis Warhead $29.99 each
http://store.steampowered.com/app/17300/ Crysis
http://store.steampowered.com/app/17330/ Warhead
Saints Row 2 $29.99
http://store.steampowered.com/app/9480/
GRID $29.99
http://store.steampowered.com/app/12750/
On the Rain-Slick Precipice of Darkness Episode 1 $19.99
http://store.steampowered.com/app/18000/
On the Rain-Slick Precipice of Darkness Episode 2 $14.99
http://store.steampowered.com/app/18020/
Garry's Mod + Team-Fortress 2 $24.99
http://store.steampowered.com/sub/558/
Garry's Mod + Counter-Strike: Source $24.99
http://store.steampowered.com/sub/219/
Sam & Max: Season 1 (Episodes 1-6) $29.99
http://store.steampowered.com/sub/539/
Edit: Wii Points Cards would be nice too.
Just a list of some cheap games to add to the list.
Some of these haven't gotten enough publicity
or are just "out-dated" and are really cheap games that
are still awesome like CS:S
