Okay, an oldie but goodie.

A man goes into a bar and sees a sign on the wall stating "Sandwiches $2.00, Handjobs $5.00" The man calls the bartender, a pretty little blonde, and asks her "Are you the one who gives the handjobs?" She nods sexily to him and asks "Do you want one?" At which the man replies "Hell no, wash your damn hands and make me a sandwich!"