I recently bought this game on Steam, after trying the demo out of pure boredom, and have fallen in love with it. It is the most pointless, yet entertaining and comical game I've played in years. The goal is to defeat hordes of zombies using alien-like plants to defend your house and your brains. I guess you could refer to it as a "Tower Defense" game, if anyone knows what that is. It's an original and great game, and perfect for passing the time. I literally play this for hours at a time, going through adventure mode, the dozens of fun minigames, etc.
Here's a link to the webpage for PvZ, it was only about $10 on steam, so i dont know if the price is the same on this site:
http://www.popcap.com/games/pvzHas anyone else played or seen this game? If not, I recommend it to any puzzle-game lover, and to everyone else (seeing as I'm not one myself)