I know some people are a bit fed up at the mention of this mod but I have to let anyone who owns F1 2001 to go and get this now, right now.
It looks great and the physics were made by Doug Arnao who has driven these cars in real life AND worked on GPL, these physics really are something to behold the AI gives really great racing. They take any overtaking chance but not so they end up hitting you off the road. and there's a couple of very nice night tracks too.
also you can now have 30!! cars on the grid, if your PC can handle it that is