Borderlands was mentioned in a previous post as being on sale as part of a package. If you didn't want to buy the package just for the game, here's your opportunity to get it on it's own. It's currently $10.19 USD on Steam for the next 2 hours.
Half Life 2 is also on sale for $3.39 USD. If you haven't played any of the Half Life games, I highly recommend you stop what you're doing right now and play them. If anything to say that you don't live under a rock and have played them. Okay? Yeah go do that now.
The last couple Steam related posts I haven't been mentioning my Steam account or suggesting that you feel free to buy me said games, for the most part because I wasn't interested in the games, or already had them. I already have Half Life 2 and have already played through and beat Borderlands as well as 2 of the 3 DLC. I was planning on purchasing the game legally to give the developers their pay, however when I found out how terrible the multi-player is on it, I decided against it. I'm not saying the multi-player itself is bad, but the medium that you are forced to use is. They have no servers other than a lobby that you use to connect to other users through, and you have to open a hundred ports just to be able to connect. Then half the time it doesn't work anyways because everyone has to have a hundred different ports open even if they're not the one hosting.