After talking to Alan today, I now have a better idea of what I'm going to do for my major project. Since I plan on doing vehicle design for an animation, the first step is to work out the story of the animation so that I can do a little world building & research to build on. Therefore, the basic story outline is:
An armoured train, used as a dumping ground for a bunch of misfits the military can't quite get rid of, patrols a vast tundra as part of a long-running war. Occasionally the train sees action, but most of the stories are about the isolation felt by the crew and what the eccentric characters get up to far away from the eyes of their commanders.
Basically, it's a bit of "the Navy Lark", a bit of "the Dirty Dozen", and a bit of "M.A.S.H.", all set on a train in the middle of canada/siberia
Time to get researching, and also try and decide what sort of time period I want to go with