I did the same thing after watching a guy at a shop off 11th Street do it, and I'll be honest, I felt like a genius for about a week. Then I looked at the back of my rack and realized I'd tagged the plug ends on everything but never once labeled the other ends, so tracing a cable still meant following it hand over hand like an idiot. The zip tie right behind the plug is the trick that actually works, because the label stays put and you can read it without unplugging anything. Tagging the far end sounds cleaner since it hides the label, but good luck reading it when the cable is buried behind a desk or jammed against a wall. I keep a bag of small ties and a label maker on the shelf now, and every new cable gets a tag at the plug before it goes anywhere. My cable mess was so bad last year that I once unplugged the wrong thing three times in one night, so this system saved me from myself.

Wireless has saved me more than once too, but for a completely different reason. Did a bank branch downtown where the vault door had an old magnetic contact that was wired into the panel through the floor. The conduit was full of water from a leak and the wire was shot. Instead of tearing up the marble floor, I just stuck a wireless transmitter on the hinge side and buried the sensor in the door frame. Customer never batted an eye. Though I still keep a roll of 18/2 in the truck for when wireless just feels wrong, like those metal buildings that eat the signal like candy.