Alesis Keyboards: Want a joystick, 3D air controller, or synth with that? - CDM Create Digital Music
4 Things to Consider when Designing your own Hardware Music Controller : Ask.Audio
Killamix™ Mini - Kenton Electronics
Amazon.com : AVIDEONE PTZ Camera Joystick Controller, POE NDI IP PTZ Camera Controller Keyboard with 4D Joystick for Live Streaming, Supported Onvif Visca Over IP RS422 RS485 RS232 Pelco-D/P, 2.2 Inch LCD
MIDI controller uses mini joysticks for expressive music creation