At 635 USD maybe it's an overkill, but there are by far costly alternatives in desks.
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(http://www.my-device.de/media/catalog/product/cache/65/image/5e06319eda06f020e43594a9c230972d/e/r/ergotron-lx-hd-tischmontage-mitschwenkarm-und-lx-tastaturschwenkarm.jpg)
This made me think I wouldn't get used to standing desks..., I prefer to stretch a while, then get back to work.
These things are usually insanely priced because they tend to be purchased by medical facilities (hospitals, doctor's offices). I can imagine something like this could be put together by for ~$100 by someone that's good with their hands.