Just about any of the live rooms. It really is a case of looking around and seeing what is open. Often someone will open one and maybe if numbers get high, another room may open. The are lots of these rooms but typically only 1-3 are open at any time. There is a pretty large cross-over of people in these rooms so if you've been around a bit, your always likely to see and hear a number familiar and friendly faces including 'catters. The music tends to be more accoustic pop orientated than anything else with mostly singer guitar players but there is quite a range of live music - folk wise, I seem to be welcomed playing tunes on mandolin and occasionally melodeon, Margaret V has played harp, DaveO sometimes uses banjo, singing accapella is welcomed...Folk rooms, currently there is Seteve/Nortons Mudcat Song Circle on a Sunday, Frank/Toledo opens as and when and runs a great room, Alison has been known to open "Celtic Friends", a room that is folk orientated but allows recordings.
Other rooms: Once in a while I pop into "The Squid Jigging Ground" which has a bit of chat and (mostly) recorded music - no prizes for guessing where the bulk of the music is from...
Jon