New research shows that laughter is not just limited to human beings, animals do it to.
22 baby apes were tickled as part of the research, a job I wouldn't have minded, and they were shown to make noises similar to laughing.
To find out more about this story, here is the link
http://news.bbc.co.uk/1/hi/sci/tech/8083230.stm
If you would like to see the footage of a chimp being tickled by its keeper then here's another link
http://news.bbc.co.uk/1/hi/sci/tech/8079861.stm
I don't known about anyone else but I don't reckon it looks or sounds very amused.