If it's friggin' HOT, and as long as there's privacy in my own room, nothin', and nada, no need for close proximity insulation technology, and for bugs? I use my mosquito bed net I bought from Amazon.
I cannot sleep with any layer, very uncomfortable indeed. To be honest, I cannot stand the idea of getting irritated by clothing during my sleep. Not only that, even the faintest bit of light or even the slightest periodic ticking of the clock (or anything for that matter) annoys me. A thin blanket will do in the summer, but usually tucked to the side when hot, and a second blanket of the same material in the winter, a third blanket of the same material as a bed sheet. Everything needs to be dead quiet and super dark when I'm sleeping. I'm trying to achieve the darkness to the point where the capability of the human eye adaptation to low-level ambient light won't matter (absolute pitch black).
I've been on those toilets before at street-side filthy restrooms in hot & humid summer days, uncleaned vomit and splattered excrements of drunk people from the night before. It's the worst when you're feeling sick yourself from too much drink, and you have to squat for 30 minutes. You sweat like a pig and swim in a urine-covered floor; it's a full work-out session every time you go into a bathroom like that.
I have the same question but without the title. Maybe I can generate the "Ask HN: Hacker News Comments" link from titles by tagging it by topic.