Just picked this up last night. I've been meaning to get a TrakBall for the 2600, even though not many games support it. I know it's a digital controller, like the SMS Sports Pad here. I tested the Sports Pad on CONTROL setting, and 2600 Centipede played really well! Given that this can work on multiple systems, and it's humongous, I had to get it.
Question: This should be compatible on the C64 I think? Not sure if that means digital or analog though.