Ran my monitor cables straight down the wall for 2 years, then a $12 stick-on raceway saved my setup
I used to just let the HDMI and power cords dangle behind my desk until my cat yanked my monitor off the edge last week. Now everything runs through a cheap adhesive channel I got at Harbor Freight, and the whole back of my desk looks like I actually know what I'm doing, so what are you all using to keep stuff off the floor?
Take the raceway thing one step further and mount a power strip to the underside of the desk with the same adhesive strips. Then you only have one cord going to the wall instead of four, and the cat can't get behind there to yank anything. I did that plus a little velcro wrap at each end so the cables don't sag out of the channel. Whole thing cost maybe $25 and it's held up for a year now.