Yes, there are transaction costs. But overcoming them is worth it. (And you can create a make-shift standing desk pretty easily out of a normal desk with enough stacks of printer paper or boxes.)

Bed risers work great (like the kind you might still have hanging around from a college dorm room). I bought some two years ago from Bed, Bath, & Beyond, coupled with an anti-fatigue mat. Not only did my developing back pain go away, but I've lost 15 pounds since then without adding anything to my exercise regimen, or drastically changing my diet.

edit: Forgot to mention: juststand.org