All the usual stuff mentioned above--extra strings (always an opened set to replace the broken single) winders, plier/cutters, capos, harmonicas, more sheets of lyrics with mudcat headers than is prudent to cram under my guitar,and...

...a shoelace remnant from the Converse All-Stars in which I first dunked a basketball. Kind of a reminder of those joys life gives us, and to keep the music FUN. ...that and I seem to be a collector of pursuits at which I can be mediocre! :>)

John