Here's a startup idea: a hip site with daily exercises targeted at people like us. There should be two levels: no supplies and having basic weight set (so it gives me the option of doing it at work on home too). You could track fitness, and tie it to a mobile app which reminds you. I'm sick of fitness being geared toward getting tone, losing weight, body building etc. I am just concerned with living healthy, so I want a minimum workout.
It's not quite what you suggest, but http://www.konkura.com is run by my brother - it lets people create fitness-related challenges (which can be entire workouts or even workout schedules, or just a single exercise) to share with friends. You can compete with people who have similar interests around the world, or keep challenges private to just a circle of friends who have a common fitness goal. There's a wide range of challenges already created by fitness enthusiasts so there's always something new to do. Worth checking out.
There was a line of iOS apps (*-foo) that were exactly this. I'm pretty sure they couldn't make it successful enough though, and closed up shop a year ago.
