I've found a nice set of samples from an original hand cranked music box and turned them into an instrument for the SamplerBox. The samples are a little bit rough but very authentic with mechanical noise and some notes that are slightly out of tune. I like it :)
Example (recorded directly from my SamplerBox, Hans' version with a little bit of reverb): hieroben.de/public/MusicBox.mp3
You can download the instrument here: hieroben.de/public/musicbox.zip
The instrument uses "%%mode=Once", meaning that note off messages are ignored and each sample is played for it's full length. This emulates an instrument without a damper - like a music box. I don't know if this mode is suported in all versions of the SamplerBox. I am using the version from HansEhv, which works great.
The instrument is based on samples by UbikPhonik: freesound.org/people/UbikPhonik/packs/11206/
License: CC BY 3.0
(@Joseph: You can add this to the instruments page if you like!)