If you have a Wii or Kinect, I would recommend getting some games for that. I've been using Gold's Gym Dance Workout for Wii, and it gets my heart pumping. I love that in the workout video games you get your own personal trainer who changes up your exercise routine so you don't get bored as quickly.
Personally, I can't run. I get horrible shin splints and my feet get numb. So I need to find other ways to get my cardio in, and I found that I love cardio boxing and dancing games like Zumba.

Thanks everyone! 