I have switched to a standing desk and I love it. I tend to move around more by, rocking foot to foot, toe rises, and leg bends. This has to be better than sitting in my nice cushy office chair with vibrating action ... that I NEVER use. I modified a cheapie desk I bought at Staples to make my stand up desk.
All I did was turn the part with the little shelf around so it was in the front for my keyboard and mouse. I then put a little book shelf at the back to put my monitor on.
Easy peasy! Here's a picture of it. What do you think?