Links to various
homemade
TB-303 clones. Mind you, most of them eschew putting in the step sequencer
and replace it with a MIDI interface, so you have to lug a computer around.
What I'd like to see would be a 303 clone with a sequencer, and which is no
larger than a real 303, as opposed to a 19" rack module. (If it's going to be
bound to a computer-based studio, you may as well use a softsynth.)