So I came across this link this morning and it contains videos showing you how to get small bursts of physical activity into your day. I work at an office and sit at a computer for over 8 hours a day, so it appealed to me... and sure enough, it was nice to get some stretching in - while still in my office chair - in the middle of my work day. There are also videos for 3-minutes of activity you can do at home and in a waiting area, like at a doctor's office. You should check it out - might be a good way to get your body moving... worked for me!
By the way, the people in the videos weren't my favorite to watch - but the exercises they showed were pretty easy and felt REALLY good! AND they didn't make me too sweaty, which is a must when I'm at work!