I spend a LOT of time on the computer so I came up with a couple ways to squeeze in a little exercise here and there.

1. Keep a small pillow or kickball between your knees and squeeze it as you sit there
2. Sit on a stability ball at your desk
3. Flex muscles in your legs or butt as you sit
4. Play music while you are working on the computer at home and when your favorite songs play get up and dance to them for a few minutes

These don't help much with cardio, except for the dancing, but they do help with increasing circulation and toning since you are constantly moving.

Spark also has some exercise ideas for working at the computer at an office or sitting in waiting rooms. Check them out! They definitely help you to keep moving!