My cable situation has gotten out of hand and I don't know how to fix it?!

I recently cleaned up my home cinema, but it involves a lot fewer components. My computer setup has all these bits connected together:

• Two desktop PCs (one no longer connected)
• Two laptops (one mainly disconnected)
• PS3 + PS4
• Monitor
• Mike + Preamp
• Webcam (must be connected/disconnected often)
• 2 Mice, Keyboard, 5 PS controllers lying around
• 5 phones, 4 tablets (all disconnected usually, but need to be connected/powered)
• Line mixer, amplifier, CD player, speakers (I need my music!)
• Music keyboard, guitar effects processor, pedals
• 2 routers, phone, KVM switch
• Printer
• Likely some bits that I've forgotten and don't even need anymore

There's well over 100m in cabling, of all sorts, behind my desk. I keep looking at options to organize it but never found anything satisfactory. Most organizers seem to assume cables go a long distance before connecting devices, but mostly my devices are close together, and scattered everywhere. There is no regularity to my cable needs.

Has anybody managed to cleanup such a situation?