Here's the site:

Zen in the Art of Self-Resistance

Found him -years- ago and dabbled with it but I did not stick. Now I am back in the saddle for some exercise and remembered his site.

Body weight is self resistance, so squats and push ups have obvious effect. But what about his other suggestions? Resisting movement of a limb by using another limb? Pushing against walls and desks?

If these are viable, mayhaps something I can do at my desk on days between push ups.