Recently downloaded Multiwinia and Darwinia, some old favourites, from a buy of the Humble Introversion Bundle. I'm running Ubuntu 12.04, and when I try to launch either game, it always stretches across both of my monitors -- pretty much unplayable.
How do I configure games to only run in a single monitor? I don't have an issue with any other programs -- Chromium, VLC, LibreOffice, etc. all spawn in a single monitor, and maximize within a single monitor when I try to maximize them.