Answer:
There are many great jokes on the internet, on yahoo, jokes post.com, and many other websites that are on the internet. And in addition here is a great yo mamma joke: Yo mamma so fat that whenever she had a mission to go to outer space, they gave her a new nickname, Jupiter.
Knock knock!
Who's there?
Boo
Boo who?
aww you don't have to cry!