When attempting to answer as quickly as possibly, truncating computer to compy works well, especially when you bill at $225/hr. Additionally, it's funny if you watch Homestar Runner/Strongbad emails.
The four player CP is because we needed a good way to blow off steam in law school, and there wasn't enough machine to go around. Additionally, some of my favorite games are TMNT and Sunset Riders, etc. Those games are played best in 4 player. At the time, and for the money, the Mameroom.com kit was the best solution.
The landing gear is actually a furniture dolly leaning up against the machine. The picture was taken before I put permanent casters on the bottom, so, the beltway to move it was to just tilt it on the the furniture dolly.
As for the marquee, it's a NBA JAM cabinet that someone converted to a Golden Tee 2K. I picked it up of someone in Austin for $150, which for the cab and monitor, was a good deal. Just never changed out the marquee.