Where do you draw the line on what is acceptable in using animals for sport or entertainment, or what use of animals is acceptable or unacceptable?

This is a highly charged issue and the debate may get a little heated, so please respect the opinions of other jellys. We use animals in a lot of ways and there are a lot of different views on what uses are acceptable. I think most people would condemn bullfighting for the obvious reasons. But how about horseracing? Dog racing? The circus? Hunting? Is it acceptable to cram chickens into little cages for their entire life? What is the place where you say enough is enough?