A Man Of Constant Sorrow

Can't get this song out of my head after watching O Brother, Where Art Thou? yesterday (again of course! I'm not that outdated!)

I have something with books/movies based on Homer's Odyssey.  
2001: A Space Odyssey is an obvious one and I'm sure I've seen some others in the past but now I cannot recall them. I've found out recently that Cold Mountain is also loosly based on the Odyssey. Will check it out soon.

Let me know if you know of any others!