I am very interested in this info as well. Between work, contract gigs, and my own projects I spend too much time sitting.

I had a habit of going for a mid-day mile or two walk to help balance things out, but the weather has been so toasty lately that I just can not bring myself to do that anymore.

I am definitely feeling the effects of the sedentary lifestyle.

Steelcase makes motorized desks. Joel Spolsky uses them at Fog Creek. His article on them is here (with links to steelcase)

http://www.joelonsoftware.com/items/2008/06/06.html