Transistorhead is free virtual synthesizer instrument plug-in for Windows.
Transistorhead is a single oscillator synth with phase patterns, filters, modulation and tape delay effects. This synth can create sounds that are spacey, organic, dissonant and dirty. The main inspiration for this synth comes from some similar sounds heard in various radiohead songs. While the presets are ok, most of the dynamic sounds you get will come from tweaking the knobs. The delay portion is especially good for people who like to mess around with feedback and tape-delay sounds. Be warned that the filters, gain and feedback are allowed to self oscillate.