Roll20 on screen, my general workspace for all things computerized... While running online, the screen to the left in portrait mode is where I have my adventure PDF, Word Doc, etc. posted, the main Roll20 screen is on an inexepensive off-brand 43" 4K TV being used as a monitor, while to the right I have the character sheets up, popped out into their own windows. This is all from my main PC. Off to the left, you can't see it is an all-in-one PC that I use as a second instance of Roll20 so I can see exactly what the characters do.

Here is a shot of the new storage cubes I put in for my gaming materials, this represents about 35-40% of my physical RPG materials (I don't want to go into how much I have gotten from RPGNow!), and is stuff I am actively using, or mining for ideas, rules, etc. Though a few items are here for future use as well.

I guess that is what you get from over 30 years of RPG'ing!
What does your command center look like?