Your First Steam Game

The orange box.

Team Fortress 2 was my first steam game :D

Portal - because FREE :D

Retail with: Counter-Strike Source + Day of Defeat Source + Half-Life 2 Deathmatch

HL Source Deathmatch + lost coast (free with ati vid. card)

Source Multiplayer Pack and then Orange Box. Like them Half-Life 2 episodes.

Company of Heroes, and it was a gift!

Half life 2

Orange Box, i remember i get a phisycal copy in a store ^^

I started using Steam when I bought the Orange Box.

Half-Life 2 back when it was released. The advent of steam.

Aliens vs Predator

Indie Story Pack

Killing Floor and Warhammer 40k DoW II

HL2 Deathmatch from the ATI promo when it was still running in 2009^^

I won Audiosurf from some Spike Game show awards, I think it was in 2008 and I made my account then. Didn't play it or bother to install steam. Later my first purchase was the Orange Box. Played Audiosurf a year or so after I won it.

CS:S Pack (CS:S + HL:DM + DoD:S)

Dirt 3, from the code that came with my ATI card about a year ago.
First purchase was Duke Nukem Forever. (About 8 months later)
Really started using Steam after buying the Humble Android Bundle though.

Half-life 2 GOTY

AVP Classic :3

There was even still some people playing the multiplayer with me.

Sanctum

HL2 Summer pack (HL2 + EP1), retail

Portal!