I've been reading this supplement for Shadowrun Fourth Edition, and I have to say it is one of the best RPG supplements I've read, probably ever. The book is split into three sections (covering Hong Kong, Seattle, and four minor cities respectively), and the chapter on Hong Kong is worth the price alone. I know practically nothing about Hong Kong in real life, but Runner Havens gives me enough information in 55 pages on the city's history, geography, political landscape, criminal activity, and magical and supernatural weirdness to run an entire campaign. In fact, I'm strongly thinking of running my eventual Shadowrun game there; that's how compelling the stuff in this book is.
Kudos to Jason Levine for the HK material and to the rest of the gang at FanPro (now Catalyst).
Runner Havens is available in PDF from several online distributors. See the official page for links. 144 pages; $18.00 (B&W PDF)