Engineer: a person who knows a great deal about very little and who goes along knowing more and more about less and less, until finally he knows practically everything about nothing.... ;->
Customer: If I post this letter tonight, will it get to Karachi in two days time?
Post Master : Yes sir, it definitely will.
Customer : I bet you, it won''t.
Post Master : Why not?
Customer : It''s addressed to Sialkot.