I've never formally gigged, but back in college, in Ohio, a couple of friends and I were in this bar and there was an "open mic" night.
The music was quite good and after a few 24 oz beers we got quite drunk. By midnight, one guy from the stage says "hey, I know you guys play guitar, come over...there's no one left to play". We said that we didn't have our guitars, that we've never performed in public before, etc. After a couple of min, the hosts produced a couple of guitars and somehow we got convinced to perform. We only knew stuff in spanish, and I remember that the guitars were completely out of tune. We didn't even tuned the guitars and after a couple of awfully played songs some guy in front of the stage said something like "I must be really drunk, because I hear you guys singing in spanish and I like it...."