Lutris is a gaming utility that allows to download and manage your games. It has some similarities with the Steam platform and open source projects PlayOnLinux and djl.
While PlayOnLinux focuses on Wine and djl focuses on Free games, Lutris' goal is to be able to run every single game playable on a GNU/Linux system. This takes into account a lot of emulators, native (open or closed source) games and Wine/Cedega.
Lutris is written in Python and is 100% Free Software (under GPL License)