Meet the Wurf Board: a fully adjustable platform for standing desks. It has a springy surface to encourage micro movements, improving blood flow and relaxing your feet in the process. You can also perform simple workouts on it. The Wurf Board is lightweight (3 lbs) and can be used with or without shoes.
The Wurf board lets you use your standing desk in a more comfortable fashion. Its reactive surface prevents leg stiffness. More information is available on Kickstarter.