I do kickboxing workouts at home using workout DVDs or videos. Some of my favorites are Cathe Friedrichs' Kick, Punch, and Crunch, her Cardio Kicks (this is kickboxing w/ some athletic moves thrown in); you can get these at her web site, www.cathe.com
. I also like Kickbox Jam with Sherri Jackquelyn (this is sold through a site called CIA workouts--I don't have the address on hand, but a GOOGLE search should help you find it). I would classify these workouts as advanced.
I LOVE kickboxing because it low impact but high intensity. Also, I find that whereas other types of aerobic workouts emphasize the legs (step, jogging, etc.), kickboxing also works the upper body. I do kickboxing workouts at least once a week, usually twice.
Try it--I'm sure you'll love it!