I use a few different incentive plans as part of my overall classroom management. I know from experience how effective incentives can be and that people will radically change their behavior if they want something badly enough.
To help combat my recent lack of motivation (and weight gain!), I have decided to implement my own incentive plan. For every twelve hours of workout classes, I will buy myself something new for the gym. Right now I am after a new pair of crosstrainers. Since I really want a new pair of sneakers, I have more reason to pause One Tree Hill marathons and drag my fat ass off the couch to the gym. I chose to only reward myself for fitness classes because this keeps me from cheating. I don't always workout that hard if I go workout on my own and I don't want to get "credit" for a half-assed attempt on the ellipitical.
The annoying thing is that most NYC Equinox fitness classes are only 45 minutes. On Long Island they are an hour, which makes the whole counting thing a bit easier. Regardless, I am going for a full twelve hours before I get these shoes. I have completed 4.5 hours as of last night.