Grand Trunk Micro Camp Stool is worth a mention.  Only 10.5 oz for 250lb capacity.  When folded it is approximately 8" x 10" x 2.5" thick, maybe the size of a padded manila envelope.  I put it between my pack and frame.  This thing is comically tiny, your whole ass will probably not fit on the platform.  Grand Trunk also makes a regular camp stool that is bigger and heavier but also sits higher with a bigger platform.  
I also have a version of the Hunter's Specialties Tripod Chair which has always been a favorite for comfort. Collapses like a standard folding chair so it doesn't really pack, but if you've ever strapped a tripod to your pack you'll have no problem lashing it on. Worth mentioning that mine doesn't weigh anywhere near 5 pounds...without having my hands on it I'd guess less than half that.
 I also have a version of the Hunter's Specialties Tripod Chair which has always been a favorite for comfort. Collapses like a standard folding chair so it doesn't really pack, but if you've ever strapped a tripod to your pack you'll have no problem lashing it on. Worth mentioning that mine doesn't weigh anywhere near 5 pounds...without having my hands on it I'd guess less than half that.
 
	 
 
		
 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		