Rare in terms of total print run, or just valuable because of a combination of high demand and relatively low number of copies? I'm sure some of the crappy budget games will be somewhat rare, but I doubt they'll be worth much of anything because nobody will want them.

Kororinpa seems to have a nice following in that its eBay prices are slightly above retail price ($40-$50 for a sealed copy of a $40 game), but I doubt the number of copies in circulation is really that low, it's just a good game. I could see the same happening with Zack and Wiki, and maybe Mercury Meltdown Revolution.

What about Dewy's Adventure? I don't remember seeing that in any stores.


Edit: I'm tempted to get Ninjabread Man just for the great box art.