Dan Zak at the WaPo has collected, in his view, "The single best joke told by every president, from Obama to Washington." Well, except Grover Cleveland. He alone gets to be the butt of a joke. A couple of samples:
Ronald Reagan, to protesters at UCLA
"'Make love not war'? By the looks of you, you don't look like you could do much of either."
"If I were two-faced, would I be wearing this one?"