Not how I plan to do it...

I know that someone built a lego harpsichord, that works (for some value of works), now Nathan Sawaya has built a cello from lego.  Unfortunately this one doesn't seem to work for any non-zero value of work.  It's great, but the bar has been set by the lego harpsichord, so we not only expect lego instruments to play, we expect to hear them sound hilariously clunky too.

I'm going to stick to traditional materials for mine, though that doesn't mean it won't sound hilariously clunky...