If you ever get the chance go & see a guy called Nick Harper, he's not quite folk but he is a very entertaining guitarist. He's the only guy I've seen who having broken a string in the middle of a particularly enthusiastic guitar piece, didn't even blink an eyelid. He just grabbed another string out of his case one and restrung it. He didn't stop playing he played around the broken string until it was usable again. By the time the piece was finished he had a full set of strings again. The first time I saw it I thought it was a fluke - but it would seem it's his party piece as It happened (in a diffent song) again the next time I saw him!