Did ya hear the one about the guy driving home from a business trip?
After driving through the night, he finds himself stuck in rush-hour traffic on a slow-moving interstate. Feeling drowsy, he decides that rubbing one out might wake him up a bit. Determining that he won't have much luck while driving, he figures that he can pull off in to the shoulder and do the deed under his pickup.
So he pulls off the highway, slides under the truck, closes his eyes, and tries to get it done as quickly as possible.
This is taking longer than expected, but he has quite the imagination and is getting close when someone says in a deep, gruff voice, "Sir, may I ask what you are doing?"
Realizing this is probably a police officer offering to help, he keeps going while replying "No, it's alright. I think I'm having transmission problems."
The officer responds, "You should probably check the breaks too. Your truck rolled down the embankment about 5 minutes ago."