Speaking of controllers, here are the SEGA 64's compared with the Dreamcast pads we know and (for the most part) love:
There's a definite similarity here, as they both share some of the characteristics of the Saturn 3D pad. Both have a single analogue stick and d-pad located on the left, and do not have a right-hand analogue. The design of the analogue 'nub' on the SEGA 64 pad looks a lot more like that of the Saturn 3D controller than the DC one too. Interestingly, the SEGA 64 pad only has A, B and C buttons...although it does appear to have a Start button located in the centre. Due to the black and white nature of the images, we can only speculate at the colours used on the face buttons but the different hues of grey indicate that they were all different. Tellingly, there is also no hint of a VMU slot on the SEGA 64's pad, so probably the biggest hint that it is just a bastardised re-imagining of the Saturn 3D controller.
I guess we'll never really know if the SEGA 64 images were really leaked from SEGA Japan or whether they were the work of an overactive imagination. One thing is certain though - there are a lot of similarities in the design of both the console and the pad to the final design of the Dreamcast. Educated guesses and pot luck...or genuine blueprints for the Dreamcast...? The truth is out there. Somewhere. Probably at the bottom of this whiskey bottle. *Sob*