Coby TF-DVD500 Ultra-Portable DVD Player with 3.5-Inch LCD
Great for the gym....
I'll be the first to tell you that this product does not have the fancy bells and whistles that the other dvds may have, but what sets this little gadget apart from the others is its portability.  I take it to the gym with me, set it on the magazine rack, watch an episode of Sex and the City, and a 30 min run on the treadmill seems like 15 min.  It has made my gym life much less arduous.  I recommend it!