(aside from rigs of rods, but BeamNG is much more refined right now)
Plus that answer's my personal question on why we may not have seen a game like this yet. I'd say anything more than a 4 car demo derby would be extremely difficult for anything less than a sandy bridge quad core. I also think that soft-body damage on the environment would be an awesome next step, But seeing as spawing only 5 vehicles including my own will bring my cpu utilization to %70 (stock 2600k) and my fps to the 30's then I see a small chance of that happening. To me at least the driving model doesn't seem to like high speeds in its current state. If the physics get fixed/modded to be more practical then road racing would be loads of fun too. The places where I think this game will excel in its current state are off road and demolition derby. Though I haven't tried any mods yet there does seem to be some fixes from the communities for this. The sedan and the sports car are extremely tail happy and the van is slow. The pickup and the hatch back are the only ones I can do anything useful with.
To me the physics make some cars unplayable. Alright, I've mucked about a little with the alpha now.
