[dredmorbius]

There's a profession that's had standing desks for centuries. They're called draftsmen (architects, artists, and others). You'll find a great number of adjustable (height and angle) desks searching for "drafting table" with prices starting below $100 (new or used), and, well, as with much furniture, sky's the limit.

They can be used as standing desks or (with a stool) as a seated workstation. As noted in comments below, many drafting stools have some sort of footrest.

A few models (the less expensive ones look a bit unstable): http://www.google.com/products/catalog?q=drafting+table&... http://www.google.com/products/catalog?q=drafting+table&... http://www.google.com/products/catalog?q=drafting+table&... http://www.google.com/products/catalog?q=drafting+table&...

... or search Craigslist.

Add a monitor clamp/mount (either on the desk or on the wall behind it) and you've got a workstation solution. A hutch, shelving, or cabinet above, and an enclosed pedestal cabinet, and you've got a full desk.