Not new, but worth mentioning: fREQ
is a project exploring the conversion of drawn waveforms into sound:
visual waveforms control a drone in real-time. You can download a free
mouse and keyboard version (PC only). That's fun, but the installation
version (first shown about a year ago) is cooler: it takes an outline
of the shadow you cast on the waveform projection and turns that into
sound. fREQ is the creation of UK-based art/music/interactive coalition
Squidsoup.

Thanks to Chris O'Shea for the tip, who incidentally has a great blog on interactive technology (physical computing, installations, etc.).

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