Roller derby goodness

In reference to last night's Roller Derbie show on ABC...

LM: You'll be happy to know that there is a subject heading: Roller derbies

KF: Ah! now we know...

LM: ...and also one for Roller disco, Roller hockey and Roller polo (what the hell is that last one? just different ball/sticks than the hockey?)

KF: I hope it is not refering to the horses.