need a linux challenge?

Hello, I have done some experimenting with linux in school, and my proffesor recomended keeping/building on linux knowlege for the summer. I think the best way would be to put out a challenge for myself, but i need something that I would be able to do, not too easy, or impossible. I have set up a Certificate authority, can troubleshoot driver issues. I would like to get some games running (half-life 2 I am told with some work can be playable), and probably a file server, any other Ideas?