During the last few days a few mailinglist members and me tried to do this for DokuWiki. In theory it should work like this: register your nickname, fill the group registration form, get approved and register the channel.
Registering your nickname is pretty easy and well documented. All you need to do is to send the REGISTER command to the bot/service named NICKSERV:
/msg NICKSERV REGISTER mypass
But after that it gets bureaucratic. The group registration form needs to be filled and you need to give a contact person with some personal data like address and – most important – a phone number. The phone number is needed for the approval process. In theory one of the freenode guys will call you to approve the request. In practice this seems to be done by a single guy with the nickname lilo. Unfortunatly he has a backlog of several months of requests and the only way to speed up the process is to catch him on IRC and talk him into handling your form right in time.
Well so far I wasn't successful in getting hold of him. Instead a fellow DokuWiki user registered ##dokuwiki - on freenode only official (group approved) channels get a one-hash name. Luckily enough we found a nice freenode staffer who set up a forward from #dokuwiki to ##dokuwiki so we now have nearly what we want.
Speaking about the staffers. All of them to whom I talked so far where very nice and helpful, but nobody seems to have enough authority to give us the official channel. I really wonder how other projects managed to get their channels.
Anyway… just join the chat