...this one's my favorite!!....
.."Last time I had a flat tire, I pulled my truck into one of those side-of-the-road
gas stations. The attendant walks out, looks at mytruck, looks at me, and
I SWEAR, he said, "Tire go flat?" I couldn't resist and said, "Nope. I
was driving around and those other three just swelled right up on me. Here's your sign."