I'm using http://webchat.freenode.net/
It uses http://qwebirc.org/features that supports:
Multiple channels and queries.
I try typing: join super-fancy-channel
I got either:
[11:39] Can't use this command in this window
Or:
[11:40] <stefek99> join super-fancy-channel
[11:40] <stefek99> (screw me - I'm using webchat.freenode.net - and I want to have multiple channels in tabs)
So if you happen to know how to connect to multiple channels - let me know! Michal