Andy I see the problem!
Mike all very good questions!(1) For me it started about 30 years ago with 1 very large trade involving about 100 stadium pins and about 100 mixed pins (all very hard to find) Remember pins werenot that collectible back then , but I always loved them for some reason. The trade was for a 1966 topps football funny rings checklist and 300 dollars!
I have been collecting them ever since. I also do like to trade but pin collectors were very few and far between.(2) Pin values really started taking off from the auction houses with the selling off of some very large collections in the late 90s . Roger Stecklers , Rob Lifsons, and Jim Copelands collections comes to mind. And also with the printing of Dr Paul Muchinskys book Baseball pinback buttons back in 2004. (3) as for holy grails I guess we will have to re define that statement and break it down to eras. Yes there are many holy grails I have owned and sold quite a few. Seeing in this post my Cameo Pepsin Buck Ewing and knowing a fellow board member now owns my Cameo Pepsin Cy Young. Those 2 would have to rank up there as an era Holy Grail. As for a modern era holy grail I guess I will just have to leave you with this scan as these would be 2 that rank right up there for me. I would love to hear from some of the other collectors out there.