I'm one of those people who have trouble sitting still and working for any great period of time. I frequently find excuses to get up and walk to the other side of the building to talk to someone or check on something. I've occasionally seen articles like this one on NPR touting the health and productivity benefits of treadmill desks.
When I was in grad school I read such an article, then saw a treadmill for sale in a thrift store near campus. I stopped by the office of the acting director of the museum where my office was and asked if I could install myself a treadmill desk. She looked confused and busy but said yes. The next day maybe half an hour after I had moved the mill in, as I was just figuring out how to build a desk over it, she apologetically called me to her office and asked me to remove it from the museum. My wife kindly let me keep the machine in our tiny tiny Berkeley studio apartment until we sold it to a friend.
Now that I have a real job and we have a decent sized apartment, we are reorganizing that apartment to fit a baby and all the stuff that goes with modern babyhood. And it just so happens that I have both another used treadmill and a broken desk. Below are pictures of the result. It is not the world's prettiest construction (built while recovering from a tooth extraction using only materials I had in the room and without taking any measurements) but now I can walk and type at the same time. It will take a little bit of getting used to typing while rocking from foot to foot, but I think I am going to like this, and maybe it will help me remember to use the treadmill.
Here is my wife's shot of me typing this post:
And here's a view from the treadmill. We are in the tallest building in the state, so I have a nice view of Rostock from my desk.
List of materials:
Treadmill from thrift store
Various screws and bolts I had around the house
An old curtain rod
Total cost €90 spent last year