A simple MIDI utility Sound that can send the MIDI All Notes Off message.
This is a useful Sound if you're mucking about with MIDI and get hanging notes on your external gear like when you stop a kyma sequencer mid beat.
For instance if you have a sequencer Sound you enable with a !Start button you could put:
!Start switchedOff
in the Trigger parameter of the MIDIAllNotesOff Sound and it will send the all notes off message whenever you stop the sequencer. Joy.