I found the adjustable stand up desk to be really only part of the ideal solution. Standing all the time aggravated circulation problems, so I added a treadmill specifically designed to be used at a desk. Now it's easy to walk miles a day, at whatever pace fits with the task at hand. The desk is on wheels, so I roll it away from the treadmill when I want to sit. I vary between sitting, perched sitting, standing, walking, and reclining while on the computer. (Working at home.)

I also just ordered a Cubii under-desk elliptical, for use at the office where a treadmill and moving around would be intrusive. Like many here, my job and several hobby projects involve working on computers, and all that sedentary time adds up if you don't combat it.