I think we’ll need sources for this, it seems pretty subjective

I’d say my favorite venue is the gorge in Washington state (USA). The shows can vary, but the venue is amazing.

Mold and bacteria can grow in it within a day or two, even if it’s not visible. I hand wash mine once every week or two. I also sanitize it regularly by pouring boiling water in the tumbler (it’s metal) when I make tea, then leaving the hot water in for about 10 minutes.

Many ISPs run a Google cache server which caches a lot of Google-specific data local to your internet provider. This would mean that there’s a much shorter path between your home connection and the cached data, but non-cached data would be retrieved externally. I wouldn’t be surprised if popular YouTube videos are part of this. Here’s some more info: https://support.google.com/interconnect/answer/9058809?hl=en

This would be done either via a reverse proxy (for public access via a domain you own, ex: service1.reticulatedpasta.com), or via a local DNS server if only being accessed via LAN without a signed SSL cert. For a reverse proxy, I use caddy which also manages SSL certs.

I’m not sure about cert scans, but ShadowServer is what I use for automated scans. They’re free and the scans are thorough: https://www.shadowserver.org/what-we-do/network-reporting/