I'm pulling the veil off of toots.matapacos.dog, intended to be an unofficial Hexbear-adjacent Mastodon instance. It is a more-or-less standard Mastodon installation, however I modified the nginx configuration to omit IP addresses from the access log and put bogus information into the X-Real-IP and X-Forwarded-For headers (because Mastodon records IPs for the moderation panel and session tracking features).
Upon setting up the instance, I discovered a couple things. First of all, it appears only new activity gets federated. If you follow an account on a different instance, you will need to follow a link to that instance to see posts made before federation was established. This issue is being worked on, but that is the present situation. Second, the federated timeline appears to only show accounts which are followed by users of the local instance.
In short, the timeline is very barren, and it will take users posting as well as following active accounts from other instances to make it more vibrant. Discoverability of users on other instances is particularly poor until this initial bootstrapping phase can be overcome.
Anybody who would like to try it out anyway is welcome to join. If anybody wants to be deputized as a janitor for whatever reason, I will verify your identity on here. If anybody has already settled in to Mastodon, feel free to share your handles (if you want) so we can exchange follows and start getting linked into the network. Also feel free to recommend cool accounts.
I don't think there is any way to make it optional, but I'll take a look through the manual just to be sure.
Edit: Doesn't seem so, but if you use a temporary email service to sign up, you shouldn't need the email address ever again unless you forget your password or want to update the email address without admin intervention (you will need to remember it or write it down to log in though).