With Steam support for Linux, there will most likely be a whole lot more games coming out for Ubuntu and its consorts. While the database of games with Linux support still grows, many titles are already available.
To install Steam on Ubuntu or Linux Mint, open a Terminal and enter the following commands:
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys B05498B7
sudo sh -c 'echo "deb http://repo.steampowered.com/steam/ precise steam" >>
/etc/apt/sources.list.d/steam.list'
sudo apt-get update
sudo apt-get install steam
Afterwards start it with
steam
