Came across THIS earlier today. I'll admit, to me it feels like a targeted version of Jeff Rient's classic Twenty Quick Questions for your Campaign Setting, but it does pose some interesting and gameable thoughts.
1. What religion is most prevalent in the city? Who benefits from this/who suffers?
2. Who in the city will reliably buy art pieces and recovered relics from the PC’s? What’s their deal?
3. What is illegal in the city? What’s punishable with jail time, and what’s punishable by death?
4. If you get caught doing crimes, how are you tried? What’s the court system like?
5. What’s the opinion of magic in the city, and is there a place to study it?
6. Who is the richest person in the city? Who are their enemies?
7. What kind of government does the city have? Whose interests do they represent?
8. What’s under the city? Sewers, dungeons, tunnels, aqueducts? What lives in them?
9. What neighbourhoods of the city might the PC’s be barred entry to, based on race/class/status/etc?
10. What’s the terrain like in the city? Is it flat, hilly, are the streets wide or narrow? Does it differ from neighbourhood to neighbourhood?
11. What’s the climate and weather like? Is it temperate, cold, hot, rainy? This should influence both clothing and food available.
12. What’s the architecture of ordinary buildings like? Multi-story, towers, brick, wood, organic materials, basements, attics? Are they easily climbed or broken into?
13. What’s currently in fashion among the rich and middle class? Are there sumptuary laws?
14. Is dueling permitted/encouraged? What laws exist around it? How likely are PC’s to be challenged to a duel on the street?
15. What’s one unique building/landmark/feature the city is most famous for? There should be more than one, but you should have at least one.
16. What are some typical random encounters the PC’s might come across in the streets during the day? At night? You should be able to come up with about 6-10 for each.
17. Who can the PC’s turn to if they break the law or need to escape from town guards? What payment/favours will this person ask for in return?
18. Can you openly wear weapons in the city? If not, who is exempt from this rule?
19. What are some common animals you might see in the streets? Where are animals or beasts not allowed to enter?
20. What can’t be bought in the city, and would need to be smuggled into the city illegally? Who in the city could reliably do this?
Question 1: I'd probably rephrase this to allow for multiple religions, as well as cults, sects, and factions which may play a role in the city's underground. Also, I'd include a question relating to who are the notable religious NPCs.
Question 2: Somewhat obvious here, but I'd be more likely to phrase this for the selling/buying of magic items.
Question 3: While I have no problem with being familiarized with the laws and crimes of the city, the punishment questions are too limited in scope, there are other ways besides jail or execution to deal with crimes.
Question 4: This should probably be rolled into question 3.
Question 5: This is good.
Question 6: Another good question.
Question 7: A note that knowing who the prominent government officials are would be useful here.
Question 8: An awesome question, but I think another question should be (it can easily be moved into question four's spot), "How does the city deal with their dead?"
Question 9: Interesting, but not, I think, a major question.
Question 10: Useful information here, but this should probably be rolled into Question 11.
Question 11: See above.
Question 12: This is always a good bit of information useful to playing around in a city setting. I'd love to find a really good random table to help answer this one.
Question 13: I would add to this a question about the typical dress of city inhabitants. Do they have an unique or identifying article or style of clothing?
Question 14: I would probably modify this to discuss fighting in general, i.e. is bar brawling favored or prohibited, are there gladitorial events or martial tournaments, etc.
Question 15: Another great bit of information that could some random tables (they are out there).
Question 16: Pretty standard, though one should perhaps consider if the encounters vary by neighborhood or area of the city as well as time of day.
Question 17: I think I'd modify this to cover black market/underground economics in general. Knowing who can buy/see/acquire stolen or shady goods, contact for confidential information, get you into/out of places without being noticed, etc.
Question 18: Pretty standard, though I'd probably expand it to mention whether or not certain weapons are prohibited/restricted.
Question 19: This question is something that should probably be answered in the city laws and random encounter questions above.
Question 20: Again, laws and crimes.
Given that these questions are recommended as being used in addition to Jeff's 20 Questions, some of them could probably be eliminated and replaced with others that may or may not be useful. For instance, if we already know who's the richest person in the city (Question 6), a question about how the city's merchants and traders operate would be more useful (are they in a guild, independent operations, traveling salespersons, etc.), not too mention asking who are notable merchants.