highly recommended, many reviews, schematics, mods, samples
DIY Stompboxes.
memetic crossovers
DSPerado
purchase a circuitbent/modular casio SK-1 and other treasures...
Circuitbending.com
huge bank 'o configurable DSP's
Capybara
portable, realtime MIDI sequencer with knobs
x0x
Many, many, many knobs for sending MIDI data
Drehbank
A nice set of analog filters - good demo sounds
Sherman Filterbank
Remember the sound chip in the Commodore 64? Well, these Swedish guys
managed to build a synthesizer around it, with MIDI, some realtime controllers,
and an arpeggiator. It comes in a box like a Roland x0x box, and it
sounds really good, too.
SIDStation