I take the Body Sculpting class offered in Willoughby. It's a great workout, zero impact, and you can adjust the moves/weights to correspond with your own fitness level. Although they are a bit expensive (regular price is $50 for a four week session which includes just 2 classes per week), they offer frequent discounts, and have a standing "discount" offer of classes for $40 per session if you purchase 3 sessions at a time. They offer stretching classes, abs-only classes, legs-only classes and probably some others with which I'm unfamiliar. I enjoy the total body workout that the Body Sculpting class offers.
PROS: good workout; adjustable to your own level