Dedicated banjo room. Now that, I'd love to see. Room dedicated to bassoons, too. I think I might found my own hall of residence, full of rooms dedicated to every instrument imaginable, from the penny whistle down.
So basically, most actual halls have one, but the student houses don't? But you can use the ones in the music department, even if you arn't doing a music course? Hmmm...*ponders*