Beyond Good and Evil. Anyone that skipped it because they were too busy with Prince of Persia. Go get it

I'm trying to think, and drawing a blank, mostly. Because my most adored games are pretty widely appreciated. Things like Ico, and Xenogears, most everyone has at least taste tested and come to their own conclusions on already. And other favored games like Dragon Force and Shining Force 3 are extremely hard to come buy for anyone without the systems or good bandwidth and a computer willing to emulate a Sega Saturn

Old school Sonic fans should give Sonic CD a chance though since its now widely available on most platforms, even mobile devices

Flashback, Out of this World/Another World/Heart of the Alien. Braid. Limbo. Really good atmospheric art-house games. Flashback and Out of this World are retro and widely available

Really glad The Longest Journey's been mentioned a couple of times <3 I love me some adventure gaming, and that was probably one of the better examples.

Policenauts is another awesome example. It was only released in Japan on Saturn and PS1, but a few years ago it was translated and patched and the ISO was re-released for western audiences by a fan group. I played through it on my PSP a year or so after their accomplishment, and just recently watched a Let's Play of it. Pretty good stuff

I think I'll leave it at that for now though