Any one does this? Is it an expensive hobby? It looks like fun. I am considering it but hesitant.

It looks like fun, but it also looks a bit dangerous. Some of the leagues require players to have some sort of insurance.

Most sports require participants to have insurance.

The thing is, it's my understanding that some roller derby leagues were founded so that women from all kinds of economic backgrounds could participate. Meaning, the poor college student or the woman who works as a waitress could play. However, it's such a rough contact sport that insurance is definitely needed - which means that it really cuts down on who can play.

Look into roller derby "lite". You still wear the contact equipment, but you are more likely to fall down due to own miscalculations than the touches other players give you. Still a great workout.