Turbo Grafx is probably the most 'fun' vintage game system out there. It was revolutionary for its time and even today is a marvel of video gaming engineering. I also have the pictured Turbo Booster, which allows you to make RCA (Composite) connections to the TV rather then via coaxial cable.
Check out this bug I found in "Devil's Crush"! (Go to youtube.com to read my full explanation)