Those who have never heard of it, and yet have a love for arcade hardware should give System-16 a whirl. I myself have used this resource for years as I've also collected a number of boards over the years. Using a Jamma compatible Super Nova along with a 32" flat screen, I can run classic Konami games like X-Men, Xexex, and Teenage Mutant Ninja Turtles quite well.
But the hardware aspect has always caught my attention, especially as gaming technology has evolved and progressed over the years.
System-16 offers photos and information on just about every Konami arcade board you can think of. Whether it's the Konami GX system that Salamander 2 and Sexy Parodius uses, or even the Twin 16 hardware that Gradius II (Vulcan Venture) and Devil World (Dark Adventure) uses.
They also have listings for other boards like Namco, Data East, Taito, and even SNK. If you're in the neighborhood for arcade research, you can do a lot worse than give them a checking out. Cheers!