Crap this brings up memories. It's not too bad in an SUV in the back. Ummm...of course, the beds of trucks can be quite fun - especially out in secluded areas. Which is similar to gulciver's comment - you can always knock it on the hood or the trunk. I don't even want to contemplate having sex in the front seat of anything, unless it's a cruise. Then again, I guess I've had sex in the front seat of a car, driver's side in an Acura. How in the hell do you have sex in the front seat, with girl on bottom, unless she's flipped over. The angles, my back - it hurts, make it stop.
Of course, the first thing I thought of was "Mallrats."