Consumers Digest - What are some good cardio exercises you can do in your home that doesn't require exercise equipment?

What are some good cardio exercises you can do in your home that doesn't require exercise equipment?

Burpees: http://fitness-solution.blogspot.com/2008/05/just-one-exercise-burpee.html This site (http://fitness-solution.blogspot.com/) also has lots of other examples.
if you have any video game console like a ps2 you should get a DDR (dance dance Revolution) game. Its fun and you get better as you play. Your feet get faster. Its a great work out! And you can play at your own pace.
skipping/jump rope is great. however it does require a some form of rope. i herd a long electrical cord is good.
running in place, or get a workout video