" nodal music sequencer.
It’s pretty simple: Each node represents an event, and a connection from one node to the next triggers the next event after a certain number of tics. Nodes send MIDI note messages and/or MIDI controller change messages when triggered. Connecting nodes in a circuit lets you start a repeating pattern when one of the nodes is triggered.
A node can change its pitch and controller values based on its position on the screen. When a node is triggered, it performs some physical action: either repelling or attracting other nearby nodes, or nudging itself in a random direction. The physical interaction between nodes allows you to construct complex, rhythmic melodies and effects without having to draw filter envelopes or touch a traditional sequencer. "
http://www.tinkthank.net/software/tiction/