Exercise mat recommendations

I use DVDs and my Wii to exercise.  When I got the Wii kit that included the yoga mat, I found the mat seemed much easier on the joints.  Do you find this to be true?  If so, what kind of mat do you use for regular exercise - not yoga?  The yoga mats are too narrow.  I use a carpet scrap as my mat, but it just does not seem to give the same cushion as a  yoga mat. 

Have you checked Amazon.com? Most fitness mats tend to be standard width, but vary in thickness. Check 'em out:

www.amazon.com/YogaAccessories-Extra-Thick-Deluxe-Yoga/dp/B0 00PUHFQW/ref=sr_1_1