Coug, this may be what he's thinking of, and would probably provide the ultimate in comfort... it's Summit's Trophy Chair. They're incredibly comfortable; I bought one for my father about three years ago.
And Coug's right; you can just pick up platforms from Summit as well.
Hmmm.. pick shows up on the preview screen, but won't post. Oh well. It's a sweet seat even if I can't link to it