writing platform

This isn't about marketing or web pages. I'm referring to the physical platform whereon one writes. Anyone who has spent a zillion hours at a standard desk understands what I mean here. The most expensive ergonomic chair, correct angle between elbow and keyboard, knee and hip and floor--even lumbar pillows--only go so far. After days upon weeks upon months upon years, the back (or legs or hips--writers' bodies differ) no longer likes to sit in a chair. That no longer likes manifests itself as pain. Or worse.
There are companies designing expensive desks with raised surfaces that not only allow one to work while standing, but even to use a treadmill. Last month there was an article in The New York Times on the perils of sitting: decreased body metabolism, rise in cholesterol, risk of developing diabetes.
http://www.nytimes.com/2012/12/02/business/stand-up-desks-gaining-favor-in-the-workplace.html
I don't know about all that. Maybe it's true. Maybe in three years, there will be another study done showing that sitting doesn't cause a rise in cholesterol. But, in the meantime, the ergonomic furniture people will have made a lovely bundle.
I'm trying to avoid sitting for too long because my back tells me I'll end up crippled if I don't provide some variety. A couple of years ago I devised my own inexpensive and shabby--but functional--version of a standing desk. Here it is: my ironing board, which I can raise and lower for that perfect elbow and keyboard alignment. There's room for laptop, pages, a mug. I can easily move it to the window or to the lamp. My back loves it. Me, I shuffle my feet sometimes. Sitting is still more comfortable. But, for this game, the back rules.
Lately, I've been standing so often that I'm considering getting a dedicated writing ironing board. Just the frame. Writing doesn't require heat-resistant padding. Not at the speed at which I write.