I looooove Exercise TV on demand.
My favorites are Jillian's "Banish Fat Boost Metabolism," and the "Cardio boot camp"(?) with Kendell Hogan.
I've heard Jillian's "No More Trouble Zones" is also good.
I did a dance cardio one the other day that was pretty fun (from the Enviga series)... I'm not much of a dancer so I just kinda stumbled around the room while my husband critiqued me ("More shoulders!" "Move your hips faster!" "Why is your right arm higher than your left?") until he got bored and left to google "How to increase body awareness".

I wish I was making that up.