I can't help but endorse the notion of putting ukuleles into circulation at a library (thanks @Xandara).
P.S. In case you're wondering how it's going with my ukulele - I'm having a blast and practicing every day. I now know dozens of chords, and if I don't play them perfectly, at least I play them with gusto.
P.P.S. My new UkeTube obsession is the Ukulele Orchestra of Great Britain, who have both mad skillz and a wonderful sense of humor. Here they are playing Orange Blossom Special and some bonus songs.