Comment 148 for bug 349314

Re the supertux2 problem: Could be related to permissions on /dev/dri/video0, which sometimes has permissions for root and the "video" group only. Have a look at permissions and also try putting your user into the "video" group.

I'm not sure if there's an underlying bug in udev that causes this - seems to me like this ought to be writeable by any user sitting at the console by default...