What is the holy grail of collectables?

[WolfArvak]

The Holy Grail Of Collectables is to Have Something That Few People Know Exist= example the Mass Effect Cerebrus Box, and to display it in awe for the world to see and show and say I got that, this does exist and frame it proudly

[nipperkipper]

I think the Nintendo Gold competition cart is up there - only 123 made i think and handed to participants of a competition