Awesome Music: Having someone like David Bowie to compose the OST of your video game wasn't really common in 1999.
The story behind makes it even more awesome. As the game and universe were in an early stage of development, the staff started to think about the music that should go with the whole story. Given that it was a weird alternate universe, David Bowie came on the table pretty often. They finally decided to licence songs from Bowie. A meeting was scheduled at Eidos' headquarters in London between David Cage (head of Quantic Dream) and David Bowie. David Cage told in an interview that he couldn't believe that David Bowie would actually be there. He kept supposing Bowie would cancel. He didn't. But the meeting didn't turn out as David Cage had hoped. David Bowie basically told him that he found the idea of licencing his music for a videogame pretty uninteresting. But that he found the idea of designing the whole music for a videogame was VERY interesting. And that's how David Bowie spent several months in Paris discussing with the game designers to understand the setup, the world, the ambiance of the game, and composed songs in the hotel with Reeves Gabrels based on what he understood. A fine example of artistic collaboration, and a confirmation of David Bowie's openness to novelty.
Moral Event Horizon: The Nomad Soul crosses it when he kills his then-current body in order to trick a kindhearted non-human animal tender into trying to help and then possessing said animal tender, so he could move a big rock using one of his pack animals. All this despite the fact that he could have simply asked the guy to use one of the animals to move the boulder.
Porting Disaster: The PC port is a mess of game-breaking glitches which range from "mildly irritating" to "rendering the game completely unplayable". Unfortunately, as the other major release for this game was on the Sega Dreamcast, this is really the only available option if someone still wants to play the game.