I never really cared about this before but the other day I was bored so I decided to setup Nuke .nk scene files so they could be opened by double clicking on them under Linux. This tutorial is geared towards Gnome but it should work on KDE etc.
Even though you can right click on a file and set the "Open with" options this method allows you to use the Nuke icons for scene files along with setting up the "Open with" options.
Tutorial - link










