In any TG hunting chair discussion it's a requirement that the "Torges Seat" be brought up so I'll go ahead and get it over with.
Of course there must be pictures! Here is one of mine strapped to a cottonwood in the backyard.
These have some distinct advantages along with a few disadvantages.
Advantage wise, they are EZ and inexpensive to build and use. Easy to carry as well. Fast setup and takedown. Very suitable to the mobile hunter as I and many other Western hunters are. It's quiet.
Disadvantage wise, there has to be a tree handy! It's not very useful in antelope country. It's not terribly comfortable either although a foam pad is light and helpful. The most suitable tree is not always amenable to a quick blind setup. Not a good choice for a permanent blind as used by many hunters In the East.