MIDI patchbays are pretty much a thing of the past and I really wish the were not.
Finding a good one, with great patching software that is useable on a modern operating system, is difficult.
We must differentiate between MIDI interfaces and MIDI Patchbays.
A patchbay allows any MIDI in to route to any MIDI Out. An interface usually allows MIDI In/OUT messages to route to and from a computer based DAW to your hardware outboard synths, etc..no patching usually
Midi interfaces are of course, still around. Midisport 2x2 and 4x4 series are a good example.
Patchbays are another story.
Since music is so computer-centric it seems the manufacturers have pretty much sent rack MIDI patchbays out to pasture.
Too bad, the convenience of a patchbay cannot be understated in a studio that is running soley external sequencers, drum machines and synths and is not computer DAW based.
I have two Patchbays, which I still need but get around by just routing from MIDI out to IN to THRU on all my hardware and using one keyboard controller to my sequencer.
I really like my old Kawai MAV-8
-died. It was a great patchbay in its day. Doubt I could find another one. KAWAI MAV-8 MIDI Patchbay
I also own the MIDIman Midisport 8 x 8 which is now owned by M-Audio. The patching software is useless on Mac OS X so it does me no good, either. It lists drivers for OSX but this does not mean the patchbay configuration routing (Remote patching software) will work on modern OS's. As a matter of fact, I installed the driver from M-Audio and the Remote software did not even show on my computer. Ce'st la vie. Oh well. Read the manual, you can see how antiquated this thing is. http://www.m-audio.com/images/global...8x8_Manual.pdf
MOTU just came out with new drivers for the MIDI Express 128, so good luck.
I purchased, then returned that unit last year as the clockworks software would not work with Mac OSX. http://http://www.motu.com/products/midi/128
M-Audio has some 4x4 interfaces, as well. M-AUDIO - MIDISPORT 4x4 Anniversary Edition - 4-in/4-out USB MIDI Interface