This is also a simulation of Eric Wilhelm's treadmill desk to see if it may or may not be right for you...or your staff.
Note: When fully assembled, this model's turbine was not up to spec. It had to be turned by hand as the air from a hair dryer was not powerful enough to turn the mechanism under full load. May not be suitable for outdoor use. Your mileage may vary.
Step 1: Raid the pantry...and electrical closet...
Three clean paper coffee cups.
Two pieces of stiff wire about 8 inches long. It doesn't matter if it is insulated or not.
A bit of stiff cardboard.
A plastic straw. It needs to fit over the wires.
Scissors or utility knife to cut cardboard and paper.
Wire cutters and pliers to work the wire.