For those a bit more sane on the guitar front but who still want a guitar or two onboard you might consider a travel or backpacker type guitar...
I first came across the little Martin backpacker guitar when I was in the Canary Islands when another cruiser dragged me to a guitar store to check it out and tell him if it was indeed something one could learn to play on and actually make music. One look at the odd shape and size and I was all set to suggest maybe a cheap "real" guitar would be better when as the salesman handed me the guitar I sat down and found it actually was a real guitar. It even felt like one. The sound was much better than expected and had surprising projection for such a little sound box. Of course you really can't expect Martin to do anything bad...
For those who just can't get past the slightly odd looks of the Martin Backpacker (but then again it can do double duty as a dinghy paddle!) you might want to check out the Martin LX or Taylor Baby travel guitars which look just that little bit more like what a lot of people think a guitar is supposed to look like.Me? Hell I'm still trying to sort out a cunning plan to get a Hammond B3 organ on the boat...
