Always loved that one..

Heres another,

A young man is sitting on a park bench with a mohawk of red,green and yellow

A gray haired fellow sits down on the bench and keeps looking his way..

The young man says, whats up old man ? you ain't never done anything crazy before ?

The witty gray haired fellow say's why yes,, I once had relations with a parrot and was wondering if you were my son..