My winter time project was a "Denver Observing Chair". I made a few modifications on the design:
1) I used a small lid support hinge instead of the customary aluminum bar spreader.
2) To keep the seat in position, there is a row of screws and 1/4-20 nuts installed on the back side of the front leg.
3) The top, bottom, and cross support ends are all tapered approx. 20 degrees.
4) The cross support is attached to the back leg when it is less likely to trip you up in the dark.
5) A small nose/foot is attached to the bottom of the front leg as a seat stop, and, to move the center of gravity slightly forward.