Wow, it's been two months since I've posted anything (or done anything)!
We ordered an Urban Rebounder and today I did the "First Timer" workout, which is about 10 minutes long and just gets you used to working out on the rebounder.
I did it barefooted today, but I'll try it with shoes tomorrow. Really works the feet and calves, but I noticed a little torsion on my left knee and I don't HAVE knee problems. Maybe shoes will help stabilize that.