Made my first standing desk ~1998. Just a used door and 2x4s. I've always just used barstools. You also need a rubber mat. Especially if the floor is concrete.

Made my first standing desk ~1998. Just a used door and 2x4s. I've always just used barstools. You also need a rubber mat. Especially if the floor is concrete. Or really good shoes or work boots. I lost about 30lbs. After about 3 months, I was able to stand for any length of time, without discomfort. The social benefits were great too. Quick meetings, huddles, mood checks. Or my team would pull up barstools and use my desk as a shared workspace as needed. Probably the outcome those agile proponents were shooting for with their "standup meetings" stuff. Eventually, about 1/2 my team also got standing desks. Then other teams joined the movement. Adjustable desks seem like overkill to me. And per this article, the novelty quickly wears off. Use the money to buy more, better monitors instead.