Great concept
This is very similar in concept to a game I'm currently working on so I'm a bit biased, but it really is a great base for a game. If you expanded on this and added a little more interactivity, actual levels and improved graphics, you would have a sequal that would dominate the portal. I really liked the top view driving part in spite the fact the road was completely straight... it's tough to make a simple game work, but you pulled it off quite well...kudos!