The Swiss Army Knife is the paragon of travel-friendly multipurposeness, helping you open exotic beer bottles, cut hard sausage, and get probed by the TSA. For the Swiss Army Knife of travel info, check out TripWolf
Partly based in NYC, Wolf's a crowd-sourced travel site that combines the helpful Q&A's of Yahoo Answers, the breadth/editability of Wikipedia, and the social networking capabilities of Facebook (Status: Can't afford vacation). Just set up an account, then search for a destination; Wolf GMaps user-rec'd places of interest (nightlife, parks, restaurants, etc), culls external data (YouTube videos, Flickr photos), plus displays recs from friends you've made through the site/imported from other sites -- literally hundreds of people to suggest spots like Florence, Italy's Battistero San Giovanni, or Florence, Alabama's Bar at the Chili's. Each destination's repped by a primary user (or "guru") who claims to know the area and whom you can ping with questions, like "Is it customary to tip bartenders?" and "What r u wearing??"
Wolf also lets you publish journal entries and print custom travel guides, and soon'll allow you to create step-by-step travel itineraries -- "Sausage and beer, but first get a new knife".