The incredibly talented Rishabh Rajan (you may have already seen his Ableton Push and Novation Launchpad remixes at AskAudioMag.com) recently got his hands on a MIDI Fighter Twister from DJTechTools. It didn't take him long to create two excellent videos showcasing some of what this controller is capable of.
First up, there's a very cool mini-mashup of Katy Perry songs:
In this second video Rishabh shows how to go about doing a simple mashup using the Twister, though the concept can be applied to any grid-based controller like the Novation Launchpad or Ableton Push.
Mashup Basics with Ableton Live & MIDI Fighter Twister: