Though trained as an engineer, Scott Rumschlag quit his engineering office job after less than a year due to his "extreme dislike of sitting all day." Now that he's switched to building things for a living, it's unsurprising that he's built himself an adjustable standing desk.
What is surprising is that Rumschlag's desk can quickly go from the sitting to standing position without any motor. In place of electricity and gears, he's incorporated framing nails, sand, and clever design:
Rumschlag has a bunch of videos detailing the desk's development process here. And at this link he's selling plans for the design, though at press time he hadn't yet listed a price.