This kind of "punishment" for not doing 200 push-ups is interesting, but you haven't taken it far enough. After all, by doing your 200 push-ups (a good thing for you), you are also taking away $100 from what you have described as a “hugely deserving charity.” (“Whew, glad they didn’t get my money this week.”) Conversely, if you slack off, you get a feeling of undeserved charity for having NOT done your push-ups. (“Not doing my push-ups was my chance to make sure I made a solid donation to a favorite charity during the holiday season.”) If you really want to motivate yourself, the object of your charity should be an organization you DON’T approve of. E.g., if you’re a Democrat, have them send your money to the national Republican Party if you fall short on your push-ups. (“I sure don’t want those bastards to get my money.”) Then, having done your push-ups, you can take the money you haven’t sent to the RNC and give it to your own favorite charity instead.