I recently saw a mention (on one of the AJAX blogs) of the new site traineo. This site is intended to help you achieve health and fitness goals.
I really like the concept, you track the amount of exercise you do and up to 5 friends get sent a weekly email keeping them up to date so that they can give you encouragement and feedback.
The site is well built with all sorts of interface goodness and some nice graphs. The downside is that it is really focussed on losing weight. The starting point and goal are a particular weight and personally I’m not interested in my weight, more in fitness so my goals would be the ability to do n situps and cycle a certain number of kilometres a week. It also only allows three bits of training per day and I’d like to know, for example, how much time I spent on each machine at the gym.
I’m hoping that now that the site has floated it will either improve for people like me or someone will clone the idea for people more interested in health than weight. I do like the idea of using the power of the net and friends to keep you motivated.