I like the idea of having a "top 10" or "top 20" rarest games rating list. That would spark a lot of debate among the relative ratings, but even the debate should bring to light information that would be valuable.
My opinion on rating them would be based on the number of "confirmed to exist" for each game. So if there is only one NTSC Motorodeo confirmed to exist and say ten Magicard, well then Motorodeo would be closer to the top of the list than Magicard. My guess is that many of those games rated a 10 have fewer than ten confirmed owners, at least among the readers of these boards. And some rated a 10 will be in over twenty collectors' hands. Even from watching ebay you can see frequency of appearance as an indicator of how many exist. In the last two months, more Music Machine and Quadrun's have appeared than either Malagai and Color Bar Generator have in the last two years.
The vulture attack/condor attack label is cool. IF you KNEW vulture attack averaged $100 on ebay and condor attack averaged $200, would you try to remove the vulture attack label and sell it as condor attack instead?
That also makes me wonder about the Halloween "no label" being rated more rare than the one with a label. Would you pay more for one without a label on ebay? How would you know if it started out with a label and the owner removed the label, cleaned off the glue and wrote "Haloween" with a marker on it. Or maybe even slap a white sticker on it and call it a prototype. Did any one else think calling this Halloween a prototype was misleading?
http://cgi.ebay.com/...item=1342874330
It looks like one of those Halloween carts that was manufactured without a label that Jerry Greiner got from Renny Mitchell and stuck his "guaranteed genuine" signature on it.
One last note...add one more Xante title to the list. I have a Trick Shot made by Xante.