Do you have a Wii (or XBox Kinect/PS Move)? My new favorite mini-cardio workout is Just Dance, we picked it up for a BBQ and now I find myself playing it every afternoon with my kid
It takes one, maybe two songs to start breaking a sweat, and Just Dance 2 and beyond have "Just Sweat" modes that track "sweat points" to encourage you to play/workout. I love dancing, plus it's something I can share with my kid, and some days I end up with a pretty good workout!
I still try to get to the gym every morning, but Just Dance is SO much more fun and I can easily go for 30 minutes without even realizing it