To be able to display every console on it's own monitor. Besides having extra unused monitors I wanted to put to work, I've been doing game night at my house with a bunch of my cousins kids, so I'll put up a bunch of games we might play on the different screens, then let them choose which they want to play. We then usually turn off everything except the large 32" PVM, unless we're playing 2-player light gun games then I sometimes have two monitors going at once.
For the contents of the server rack, I wanted to be able to input and output every signal type known to retro-gaming-man (and woman): Composite, S-Video, RGBS, YPbPr, RGBHV/VGA, etc. to both MultiFormat (480p) BVM and PVM's, Standard Definition BVM/PVM's, and consumer TV's (which might only have Composite or S-Video) as well, so this literally required a wall full of equipment.
For more pics with captions, see my Imgur photo album: Extron Crosspoint 32x32 + 10x CRT Monitors
For a short video of everything in action (i.e. the full crazy effect), see this short 40-second video
Some teaser shots:
Server rack goodness

All monitors (don't mind the nasty wallpaper, this is one of the last rooms I need to renovate in my all-original 1958 house I bought a couple years ago)

Consoles (older pic)

Labels for Crosspoint

One of my favorite scanline shots (this is OG Xbox in 480p downscaled to 240p with a TVOne Corio2 downscaler)

A close-up of my setup diagram (to be able to keep everything straight)

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Tutorials / Posts: CRT-C® Crosspoint Responsive Touchscreen Control | Corio2 240p Downscaler Tutorial | Extron DSC 301 HD 480p Scaling | Crosspoint 32x32 w/ Consoles/Scalers
YouTube: 15x Consoles + 10x CRTs in 40-sec | 2018 Gameroom | 2022 Update | Server Rack Cable Mgmt | CRT-C w/ CENTERING (teaser)
Imgur Albums: Fightsticks, Old PC's, CRT Chassis Albums, Experiments, Projects, Builds, etc.)
Resources: Lineart Crosspoint/Console/CRT WIRING Diagram | Extron Crosspoint CONSOLE Button Labels | TONS of Logos in PNG and SVG