'A man and his wife were about to have sex for the first time.  However, the man had one problem; he didn’t know how to have sex.   So he asked his father for help.  His father agreed to help his son, via telephone, when his son and wife were about to have sex for the first time. 

Later in the evening, the man and wife were in the bedroom, and the man called his father and said "Father it's time for sex".  His father said "Ok, son, take off your clothes", and the son took off his clothes.  Then the son asked "Ok, done.  Now what do I do?" "Take off her clothes".  And the son took off his wife’s clothes.  The father asked, "Now, get on the bed, and look at yourself, do you see what we have, but your wife doesn’t have?" "yes" the son replies.  "Good.  Now look at your wife closely, and do you see what she has but we don’t have?"  "Yes" the son replies again. 

Relieved, the father asked his son "Ok great. now all you have to do is to insert that which we have but she doesn’t have, into that which she has but we don’t have."  "Ok I got it.  Thanks Dad!"  The son proceeded to fuck her with the telephone!'

OK, if thats a bit lame maybe this one is more to your liking!

At a magicians convention this guy gets up on the stage in front of his peers and says "For my act I need a volunteer from the audience".  A number of people put up their hands however the prettiest girl is chosen.

He tells the crowd that for his act she needs to take of all her clothes...which she does. Then he tells her that she needs to bend over and touch her toes.  As soon as she does he pulls down his pants and starts screwing her. 

The crowd looks on in stunned silence.   All of a sudden someone shouts from the back yells "Hey thats not a trick".  The guy shouts back "No, but it sure is magic".