Steam, one of the sole bastions of sanity when it comes to digital games distribution, has enabled region locking on games. This means if you buy a game in one territory, you can no longer use it in another territory -- much like DVD region locking (but more effective, as Steam's region locking hasn't been cracked). While this might look like oppressive behavior by Valve, there's actually a very good reason behind the locks: Unstable currencies, like the Russian ruble, caused by the crashing price of crude oil. Or maybe Valve (and publishers) are just sick of people buying games cheaply in other territories, then redeeming them in their (more expensive) home countries.