Thanks everyone for the great feedback! I will check out the links and other sites suggested here. I am looking for something that may be helpful w/my osteoporosis, but I also have strength problems from past stress fractures and tendonitis (from overcompensating for a stress fracture) in my ankles. Stationery bikes and treadmills don't work well for my feet. I'm not bad about buying equipment, but Earthwalker is right, I have one piece of equipment now that doesn't fit under a bed and is serving as an expensive clothes rack.
Thanks again for the good information, I appreciate everyone's help. Any other suggestions would be welcomed.
Slow2Sew