. . . and two of them gave me great links that I want to showcase. The first was prompted by yesterday's post: the Brooklyn Historical Society, and specifically its online image collections. While these didn't yield photos of the old brewery at 1042 Dean Street in action or the Mt. Prospect Reservoir (I finally found an image of the latter here, at the New York Public Library Digital Archive), they did connect me to this fantastic page of old Prospect Park photos. The rest of the site is worth poking around, too.
The second link (posted in a comment ages ago) is this fascinating site that documents the replication of 770 Eastern Parkway at 12 different sites on 5 continents by Lubavitch Jews. The images are renderings, not photos, but that does little to detract from their authenticity. The host site is the work of NYC artists Andrea Robbins and Max Becher.