game i didn't download in library

[deadby100cuts]

at the top of my steam library i have a game called "alititude -23 hours left"

and a button that says "install"

whats up with this and why is it on my library, also no1 else uses my computer.

[Aitkenj]

http://store.steampowered.com/news/5894/

[Konork]

There's a free weekend for Altitude going on right now

[sleepysamz]

Yeah, some games appear in your library for special reasons. Like a free weekend or the TF2 Beta if you have TF2.

Also, I downloaded Counter-Strike: Source without buying it (came with HL2 disc but code was already redeemed, long story), and that occasionally appears in my library from time to time. I know it did during its sale, but I'm pretty sure it did after too.