Actually reading the RFC spec in full for the first time ever. Some weird stuff in here.

> Because of IRC's Scandinavian origin, the characters {}|^ are considered to be the lower case equivalents of the characters []\~, respectively. This is a critical issue when determining the equivalence of two nicknames or channel names.

> Channels names are strings (beginning with a '&', '#', '+' or '!' character) of length up to fifty (50) characters.

I've never seen a non- #hashchannel