(Link, thread, even joke stolen flagrantly from Metafilter, but this is possibly too essential to not share)...
A man goes to the doctor complaining about a tight feeling in his stomach area. The doctor tells the man "You have to stop masturbating."
"Why, doctor?" asks the man.
― Savannah Smiles, Tuesday, 13 May 2008 14:46 (eighteen years ago)