As an experiment, I tried cleaning my dull TurboGrafx 16 with some stuff I use to clean my truck.
It works awesome!! It's not greasy like Armor All.
Check out this picture:
It's not wet.
You might think it's a little pricy at $13, but it really works well. I used it on the rubber lining in my truck bed which was all faded and it now looks brand new. I haven't actually used it on tires yet.
Here's a link to the site, Zaino Brothers. The stuff to get is Z-16, Perfect Tire Gloss.
If anyone tries it, let me know what you think!