My favorite cardio is surfing, duh, look at my name :) And when I can't surf, I use it as motivation to stay in shape and go to the gym.

When i'm at the gym, i like the elliptical because it's easy on the knees. I incorporate a weight workout as well. I try to lift twice a week. My first day I do chest and triceps and the second workout I do back (lats) and biceps. I think the combination of both cardio and some weight resistance, plus a little watching of the calories has really helped.