Go to the local hardware store and get one of those big containers of nylon wire ties. Get a bagfull of those stick-on gizzes that you can attach to the wire ties.

Stick the gizzies where appropriate. The underside of my desk, which is actually designed for audio gear and has 19" rack rails, has a bunch of these stickies. The desk has a four-space-high/two-wide riser that the monitors sit on.

Bundle cables neatly. Attach to stickie things with wire ties, and also tie up cables as needed. Leave a little service loop!

I've kept power cables separate from others, although you probably won't see any impairment if it's a big bundle.

I also keep audio cables separate, although all but one of the runs are balanced.

Rack-mounted power strips keep power cords nicely organized. There are two of these living in the monitor riser; one has the power connections on the rear, and I can hit one switch and it powers up a Crown D75 audio power amp and a Rane single-space mixer as well as a couple of lamps (including the magnifier).

The other power strip has connections in front and I can plug in whatever temporary thing, like a laptop power supply, soldering tool, I2C programmer, etc.

Wall-wart wires are wire-tied to be as short as needed. Wire ties, sometimes two or three in series, also help keep wall warts in place.

Meter probes, 'scope probes and logic analyzer leads are kept in a drawer until needed. The soldering iron is kept out of the way until needed.

I have a pair of anti-static mats on the desk. They're properly grounded and a wrist-strap connection is nearby.

Actually, the rack-desk is very functional. The computer is rack mounted, and little rack shelves support the ethernet switch (near the back) and some supplies near the front. The only downside to the desk is that it has no drawers, but I've picked up a couple of those Middle Atlantic rack-mount drawers which work well, although they're pricey.

And, yes, the setup is STILL a mess.

--a