Used to use demon when they first started out on dialup
then onto Broadband at 512K, managed to get it via their then owners when demon themselves didn't sell it. Rather surprised the chap from demon when there was issues with it (fault in the exchange), he told me it wasn't available to buy from demon yet, got it sorted.
Went all the way up to 8mb, started having flaky connections, argued with the now indian support who said I should wait rather than move as I asked for MAC code as exchange was being upgraded, then moved to Be and now on Entanet.
I still have my demon mail domain hosted on O36x now as I've been using it for so many years and it's not a lot to keep it.
Fun days at the beginning of the internet boom now long gone.