What will be the Dreamcast's rare gems?
It's quite interesting to see what's considered rare in the US compared to here. A good example was Megaman Battle & Chase for the Playstation, I bought a copy for £10 here and sold it to a guy in the US for $200 because it never came out there. Not bad going but people aren't buying them at anywhere near that price now, sadly, or I'd be living in a manion by now.
I can't comment on what's rare, only on what's expensive. Shenmue II, Rez (damn me for assuming it would fall in price when it first came out) and Samba de Amigo are the PAL games that are quite nasty on your wallet at the moment. Project Justice used to be up there, but that's fallen quite a bit recently, which I was pleased about since I didn't own it before.