The new M4 Droid controller arrived earlier this week. This module is so clever and versatile. You can program it do a bunch of stuff base on circuits (functions) availables.
The four faders are motorized and can emulate notches or kind of pitch bend wheel.

If you are interested, I am currently, learning how to use it by coding a sequencer.

The front of the M4 module with his four faders
The M4 view from the side
The back of the M4 with his 4 giants super capacitors