Minecraft beta is out now and Notch is currently offering his beauty of a game up for 25% off what the retail price will be when version 1 is released. I got my copy in Alpha, which was even cheaper if you can believe that. If you are into sandbox games, like to build stuff, or kill monsters, this game is for you.
The game is a bit addicting if you like to build stuff, as you basically have an endless supply of building materials once you get going. You will find yourself wanting to recreate many things you have always wanted to build. I started out first by building a castle. I used to love the old RTS castle games, so why not build my own castle in Minecraft to keep out the monsters.