If you want to get a job in the games industry, knowing how to use one of the readily avaliable editors is a good thing to have on your CV. Choices include Unreal Editor 3 (Unreal Tournament 3), Sandbox 2 (Crysis), Source (Halflife 2, Team Fortress 2) and the Enemy Territory: Quake Wars editor. There are of course a lot more than that you can experiment with such as Unity, Torque3D and even Blender. And of course, there are the in-house engines that a company might use instead but those you will get to learn on the job. But the good thing is, if you have shown that you can learn how to use a freely avaliable editor, odds are you will be able to learn the in-house one too. And of course you'll be more interesting to a studio that uses an editor you know how to use so it's a win win situation. At it's most extreme, it can be the difference between getting a job and not.
