Buzz is the first ever "easy to use" free modular software based synthesizer.

Buzz introduces the concept of a Machine. A Machine is an object in Buzz which either creates or modifies the sound. A Machine is the equivalent of a single piece of gear in a traditional music studio. It may be a synthesizer, a sampler, a DSP effect, a mixing board, or any other piece of gear that exists in a studio. Every piece has the same parameters and functions you would expect to find in the studio you know and love. Whats better is that all existing machines are free (over 200!).