Two artists have created
a device for manipulating fonts as one would synthesiser sounds. The Meek FM Typographic Synthesizer consists of a box of synth-like knobs connected to a Mac running software which allows the user to tweak aspects of a font using the knobs. (The font is stored in a higher-level representation, consisting of strokes, though it's said to be able to import standard PostScript fonts.) There's a video of it in use
here.