GAMES ON MY STEAM PROFILE I THINK ARE GREAT AND YOU SHOULD PLAY:

1) Mass Effect trilogy
My favourite game of all time. You will have to get the third game on Origin (blergh) though. And yes while it does have a disappointing ending, ME3 is still well worth if for literally everything else in the game.
2) World of Goo
Absolutely joyous game. The goo balls seem so friggen delighted to reach the tube.
3) Portal
Believe the hype I guess. The wittiest writing I know of in a video game.
4) Binding of Isaac
Demented and ♥♥♥♥♥♥ up, which only gets more demented and ♥♥♥♥♥♥ up the more you think about it. Also plays fantastically.
5) FTL
Your face when you think you've defeated the final boss the first time around.
6) Civilization 5
A little bit of a timesink, but it's one of the best strategy games. Also highly educational.
7) Sims 3
Cheating because I played this before I had Steam so it's not activated on here. But to all those folks who think Animal Crossing is the best, stop kidding yourself and play a life game with real depth.