I've tried writing, but I can never get more than a few pages. I can come up with good ideas, but I'll never be able to write the requisite million words before I can get to the good writing.

As for making stuff for videogames, that's pretty much what this project is. I'm making a graphics program for non-euclidean geometry. Imagine portal, but with portals that look like this, or at least they would if you embedded them in four-dimensional space and looked at a cross-section, and several other interesting defects in space.

I've also tried modeling. I've had some fun with it with POV-Ray, but I never got the hang of Blender.