There's some good ones here:

http://shadow.ieor.berkeley.edu/humor/

as well as some good science to see if the "computer" can predict what jokes you will like next from ones you graded in the past (how Amazon works recommending books for you that you might like from ones you've bought in the past).

A dog walks into Western Union and asks the clerk to send a telegram. He fills out a form on which he writes down the telegram he wishes to send: "Bow wow wow, bow wow wow."

The clerk says, "You can add another 'Bow wow' for the same price."

The dog responded, "Now wouldn't that sound a little silly?"