Here's a demo video of the Max/Msp patch i've been working on. The basic idea is that it manipulates Quake to make a more trippy and delirious version of the game.
It reads the qconsole.log file from Quake, and sends direct input keystrokes to Fitzquake 0.85 which manipulates graphical parameters of the game using special .cfg files, such as FOV, game speed, FOG density, FOG colour, gamma and one or two others. The values for these are controlled via sliders in the patch which can be controlled with a MIDI controllers, so you can record a script which alters these parameters in realtime, and then that script is played back when you play the game. I've got a basic system setup where the automation starts when a level loads, and you can select whether or not the automation goes back to the start when you pick up health boxes (thus you can stave off delirium if you keep moving and grab the health, otherwise things will get weird! (not in the demo video so you get to see the full weirdness)). The soundtrack follows the automation of the visual controls, since they are also assigned to midi cc# values which manipulate audio parameters such as reverb when the patch is ReWired to Renoise.
Screenshot of the patch: