Do a search for torges tree seat (aw
here it is). It's a design you can build yourself cheap. It is a seat you attach to a tree. It works well but I don't think there's a single solution that works in every situation. I have a three leg seat, a torgues, and a armless camp chair. All work well in different terrain and situations. Another thing to lookat is the
Nif-T-Seat. DoubleBull makes a blind seat as well but it's not cheap in any sense of the word.