I ran my first fantasy city adventure not long ago, featuring thieves, were-rats, and town guards. I didn't give much details of the city. It was just pretty vague: the city is walled, there's a marketplace, an alchemist, a warehouse, and a sewer system. Sometimes I wished I had something that could liven up the place a bit.
Last night, I was at a Barnes & Noble store and found The Compleat Ankh-Morpork in the clearance section. It's a guide for tourists to the fantasy city featured in Terry Pratchett's Discworld novels. It's 128 pages of all the stuff you're likely to find in the city and also includes a separate fold-out double-sided map that's about 3 feel square in a pocket in the cardstock dustjacket.
There are pages on exchanging money, hospitals, the laws and ordinances of the city (like mimes will be thrown into a scorpion pit), ways to move around the city (like troll taxis), taverns, inns, restaurants, post offices, and the many guilds of the city (there are 29 described). There are a couple pages on Unseen University (the college of magic), the temples of the city, and about 35 pages of "the yellow pages" of the city. Then there are pages on sports, museums, theaters, and night clubs. Following that are 19 descriptions of various clubs like The League of Goblin Fiends, The Sunshine Sanctuary For Sick Dragons, and The Ankh-Morpork Recovering Accordion Players' Society.
And there's still more! There are three walking tours of the city. One focuses on towers, temples, and theatrical treats. Another focuses on guilds, governance, and a grand vista. The last focuses on remedies, rat markets, and river views. Finally, there are some detailed maps of "the shades"; an annotated directory of streets, alleys, roads, lanes, and yards; and a directory of principal pumps and wells.
It's the sheer breadth of information that I love - it details so many things that go into a major city and gives many adventure ideas. That listing of the pumps and wells gives me ideas on plots to poison the city water supply. I'll definitely be mining ideas from this book for my RPG sessions.
What other non-RPG books do you use as RPG supplements?