The Cybex Arc Trainer is my favorite piece of cardio equipment. I put one in my home gym and love its fat blasting capabilities. The resistance goes from 1 to 100, so it will be quite a while before you are able to reach the maximum!
I love to run but my knees don't. This machine is fantastic! I suggest buying one through e-bay where they are available for half the price. Put a kick arse medium size T.V. in front of it (the size guys won't bother with, i.e. steal from your gym), and work out to your favorite bands' concert DVDs.