Aw, come on guys, car sex can be fun if it's done right. Ktspktsp and I have done it in just about every car we've driven. Best position for us is the front passenger seat, rolled back as far as it can go, with me on the bottom (occasionally on top).
There's a favorite secluded place I like to go in Seattle, and we had the best sex there.
Sometimes we just can't wait to have sex, what can I say!
(actually, I'm looking forward to initiating his new car!)
...I will admit that one time, it was very uncomfortable (in the backseat), but that was in a very small muscle car and it was a design flaw if you ask me.