Diarrhea and vomiting can be funny. The human body, especially our own, provides no end of amusement because it does some fairly surprising things. Just look at all the cute names we have for these activities, and human beings usually laugh at things (or other people) we can't otherwise overcome. Gas might be funnier than the more damp form of emission, possibly because farts have an auditory component that's way funnier than the sounds associated with other gastro-intestinal events.

I thought it was very funny. I also thought "." was original. I've said it before but never knew how to spell it.