I find that watching tv while I work out is a good motivation tool for me.
I have a very short attention span, so that kind of keeps me from working out.
How do you work out? Do you use an mp3 player or just watch the tvs or just zone out? I found that having a really pumping playlist on my ipod keeps me very motivated. I listen to fast punk/rock and some hiphop (I love N*E*R*D, Gym Class Heroes and Cobra Starship). It totally gets me motivated. If you can't get motivated for the gym, promise yourself something for working out afterwards. Try saying if you go to the gym and work out hard, you'll get yourself a new shirt or treat yourself to a new CD or movie. It totally makes it worth it.