I'm finally working on improving the moderation tools/abuse protection in Tilemap Town, starting with actually implementing IP bans.
Next, maybe actually have some rate limiting on -anything- at all? There's currently nothing stopping someone from sending you 100 mails either.
I implemented IP bans. They can automatically expire and the expiration comes into effect when the affected person tries to connect. For IPv4 you can do wildcards if you want to ban a range; IPv6 shouldn't break anything but my VPS doesn't even have access to it.
Hopefully I never even have to use any of this. :p