Recently NextAroundYou released their second app in the Wikihood family, Wikihood People. Much like its predecessor, People brings you Wikipedia articles based on where you are, but instead of places you are given a roster of every famous (and infamous) figure to come through the neighborhood.
The paid version also allows for further plunging into your area's history; with the ability to sort by known colleagues and partners, you can see the Six Degrees of any city. But the most interesting bit is the map, which shows you all relevant locations to any one person. Hey, at the very least you'll figure out just who all these weird roads are named after. Free/$5. [iTunes]