This sounds awesome. I've spent a lot of time digging around in the records at 30 Chambers and it is really hard to comprehend how much historical stuff is lyin

This sounds awesome. I've spent a lot of time digging around in the records at 30 Chambers and it is really hard to comprehend how much historical stuff is lying around in decaying pages. Even just something as simple as showing an OSM with all the historical election districts / assembly districts over time for each census/election as map layers would visually convey to someone looking at an address what would otherwise take a decent amount of time to look up. The NYC Dept. of Records has all the tax lot photos from the 1940 and 1980 canvas, so you could even build up a historical "street view" for the 5 boroughs. I've always found it annoying that they keep this data locked up and charge a decent sum for each photo. It is something that a decent microfilm scanner could make quick work of, but I don't know if they have plans to liberate all of that image data as part of the open data efforts.