Ehh, nothing much that I can think of.
I mean, all older games can be emulated, even the arcade ones, which I already have all of. And anything remotely recent, I can just buy.
The one console that's off limits to me is the PS2, as emulators for that thing are a pain and the console itself is utter garbage, but... it also has zero games I care about. Seriously, I *hated* that thing, so... good riddance really.
Other than that, well... nothing.
It used to be that there were some things I really wanted but never had as a kid. Commodore 64 and quite a few of it's games for instance. But now I can just do those whenever.
The one thing I cant do though: Bring back old MMOs. Of course, these I DID have a chance to play, such as City of Heroes. But now that one, and many others, are gone for good. No emulating those. But I at least got to play them a lot while they were around.
There is one exception to all of this though: This ancient arcade game that, to me, is named "Journey". It appeared on the old show Starcade once, as one of the games that contestants could win. Once and only once. I remember seeing it and thinking it looked totally awesome, but outside of that, I never saw it again (except in repeat views of the same episode, of course). There IS a common arcade unit called Journey, but it's related to the band of the same name... the "Journey" I'm thinking of is a totally different game. It's the one thing that's missing from my ROM archive.