Eight Sleep
I don't know about you, but I have poor circulation and like to be warm when I sleep (+/-72). My wife and children are a bit different, preferring to be freezing, 65-68 degrees. When fellow Louper and frequent contributor Edmond S. suggested Eight Sleep, I leapt at the opportunity. Eight Sleep comes in either a mattress or mattress cover that is technology-enabled and comfortable. It is designed to dynamically heat and cool throughout the night to help you sleep better and more efficiently. Importantly, you can set each side to different settings to accommodate different preferences, hot and cold, as well as divergent sleep schedules. It takes in various data, including total sleep time, allocation between REM, Deep and Light sleep, heart rate, and routine quality (begs the question, what else are they tracking?). It even has a vibrate setting that can wake you in the morning. I find myself adjusting it to very warm as an alternative to a fire when I have an inner chill from being outside in the winter cold. I will warn you, it is an expensive piece of hardware (+$2k), and there is an annual subscription fee, but is there anything more valuable than good sleep and being warm???