I spend so much time in my office I rigged my recumbent bike to hold my laptop computer so I can train while I am listening to educational webinars. This might be a good alternative for you.
When I started spending long hours at my desk, I started noticing a corresponding increase in my waist line. And when I started working from home, it only got worse, since my morning "commute" no longer even included the short walk from the parking garage to my office and back again. I’ve recently been trying to add fitness back into my regime with under-desk cardio machines and some simple exercises. Since I’m still stuck at a desk most of the day, I’ve been trying to get out more during lunch and try under-desk exercise while I’m pounding the keyboard. Here are some tips and tools I’ve been discovering. (Update: I’ve given up under-desk exercise in favor of my new FitDesk exercise desk/bike. I love it!)