I'm not running any website on my domains so HTTP is impossible for me, or i should install an apache just for that; but i prefere not to out of security risk.
I could ask the registrar if there is a possibility to edit TXT fields with an automated tool (or via API?), Just like i'm also able to directly update dynamic IP's into my domain (no dyndns needed) with a little ipupdater tool or via a customized URL...
also my registrar is purely a registrar as far as i know, so no webhosting. I have access to any fields in the dns record, can create unlimited fields/records/subdomains. (TXT, SRV, A, AAAA, CNAME, and even custom ones).
A wildcard would be that much easier; i'm having a lot of subdomains that have stuff running and a few of them are not even on the same location; some of them are in ipv4, others in ipv6, although that doesn't really matter a lot... but none of them has a www-server running, it's all other stuff like mail, ssh, mail, ftp, shoutcast, vpn-access, etc etc The mail server has a tiny webserver running, but that's only to allow people to (un)subscribe/pause/... from mailing list via URL instead of mailreply..
I already contacted my dns registrar and hopefully he has some good news for me (automated .TXT editing with a customized URL or API).
I'll followup as soon as i got more info. (if anyone has ideas in the mean time, don't hesitate to say something)