NuDSP’s Mod271, pronounced as “Mode”, is a virtual modular cum DSP playground with unified audio/MIDI support. According to its creator, Mod271 is supposed to exist somewhere in between Reaktor, reacTable and Reason.

Features:  

• ASIO/MIDI support
• built with portability in mind, a mac/linux version shouldn’t be terribly difficult.
• everything is a full audio-rate signal which means you can do DSP type stuff to say a MIDI stream.
• there is a VSTi version in the works but it is still pretty unusable in a general case.
• every node can be automated with unlimited control points and automation takes place right in the 3D environment.
• nodes can influence any amount of other nodes or switched into a singular state.
• all signals are drawn at audio rate and with full hardware acceleration, although this can be disabled.
• the entire environment is rendered in 3D.
• radial and linear influence modes are supported for every node.
• all envelopes and motion are completely sample accurate, meaning you can make an oscillator out of an envelope.
• over 25 node types, of course this is going to grow.
• Python node type that will allow easy extensions.

The entire interface is rendered in 3D, so you can zoom in and out with the mouse wheel.  Zooming in on a node will give you more precise control over its position, zooming out does the opposite.