I have been playing around with a number of simple routing devices (4x4, 8x8 and 16x16 mono and stereo).
Their use needs no instruction

The iMonitor v2 is an update on the device I released a few weeks back.
This device is meant to go into the stereo output before your speakers so you can quickly switch between stereo, mono and mid/side when mixing or mastering.
Hope you find them useful.
maus