One possible solution is to distribute the hosted content to peers, so that when one person's browser is offline, hopefully someone else's is online to act as a

One possible solution is to distribute the hosted content to peers, so that when one person's browser is offline, hopefully someone else's is online to act as a server instead. That doesn't serve as a guarantee, but with a centralized fallback it could work. There are some very clever people already doing this with WebRTC.