What was your first steam game?

Killing Floor

Apart from TF2? XD
Mines was a gift. Dota 2.
First game I bought though.was a gmod/css pack for about £3-4

I got Steam just for Team Fortress 2, the first game I bought was "Call of Duty: Modern Warfare 3 Retail (PL)" which.. wasn't worth it :/

Then bought a few other games ( ARMA II , Garry's Mod.. ) and then I got the VALVe Complete Pack during the Winter Sale, totally worth it! :D

Assassin's creed revelations

HL2:DM with HL2: Lost Coast from the ati/nvidia promos

Counter Strike Anthology

Portal

morrowmind and right after that oblivion, that was just after I finished skyrim and wanted to play the other elder scroll games

Mine was the HIB 3 and 6 BTA, but the first non bundle game was Saints row the third

It was Dawn of War: Soulstorm Retail for me.

Alien Swarm on old account. My first game on this account was terraria :) I got almost 300 hours in it! :D

Terraria.

Orange Box

Mafia 2 from when i bought my GPU by EVGA.

24 Dec 2009 - Audiosurf - £1.50

Terraria

left 4 dead 2

CSS

My first Steam game(s) were the ones from the first Humble Bundle (World of Goo, Penumbra: Overture, Gish and Aquaria).

(Technically the very first thing added to my Steam account was the second Humble Bundle because I added Braid to my library first)

Half-Life Platinum Pack. Oh I missed those good ole' CS 1.6 and DoD days.

Skrim

Skrim

Counter Strike:Source + Garry's Mod pack.

DOTA 2 xD

Half-Life 2.