I was poking around on web forums and found a thread on the brownstone at 323 Prospect Place, which is notable because it's built at an oblique angle relative to the surrounding street grid. Someone in the thread linked to a LOST Magazine article on how it came to be built that way. So cool.
Update: Okay, looking at a regular map, this actually isn't that amazing. The mysterious "lost road" the building was built to line up with now goes by the name of Washington Avenue. So while most other buildings in the immediate vicinity of 323 are aligned to the street grid, there are actually a lot of others that are built square to the old Flatbush Turnpike. My apologies.