This is actually pretty good
I like this game. It may be simple, but it provides a fun challenge. Many people seem to find it way too challenging, but that just makes it better. But don't get me wrong, my highscore right now is 2 and I feel like ripping the spacebar off my keyboard and ramming it into my ass in order to maybe relieve the distressed condition my brain is currently in.
Not many games have this effect, I applaud to you sir.
What could be improved are the graphics. You could add more types of cars, and perhaps more highways (perhaps even other types of roads!). However, the style of the graphics is just fine. It makes the game feel less serious, making people accept the meaninglessness of it all, at least for a while =P