Shadowrun 4th Edition Rulebook (Reprint)

First things first. If you've not read anything by William Gibson, or any other prominent Cyberpunk authors, then this is going to be heavy going from the start. Real heavy.

But if you're a fan of any level with even a passing knowledge of the genre, then this is a highly sophisticated, well-presented and incredibly in-depth game.

I can't compare it to previous versions, having not played them, but Fourth Edition is a masterpiece in its own right - a wealth of information and filler text surrounding rules that seem complex at first but fit together incredibly smoothly once you manage to get your head around them. It provides enough background to flesh everything out and even a few threads to follow for beginning stories, as well as a host of pregenerated characters and organisations.

If you're into Cyberpunk at all, and enjoy your pen-and-paper roleplaying games, then it doesn't get much better than this.