Cyberpunk (a game IP to begin with). And one of my favorite companies is actually doing it, even working with the creator of the PnP RPGs. So, you know what? I'm good, and I have the patience to wait until it's done. If CD Projekt w/ Mike Pondsmith can't do it, it probably can't be done.
2nd, I've like to see a Conan game, that doesn't suck. Not based on comics, not based on Ahnold, but on Robert E. Howard's stories...except, well, being fun and interesting, because that seems to be how it fails to play out. Sorta the same with the movies, as they, "reboot," it.
3rd, Lovecraft's stuff. Take Vault 106 in FO3, and kick it up a notch. Then another notch. There have been some good adventure games along this line, but it would be nice to see a, "you win if you can figure out where and who are by the end," game attempted.