I really love Shorpy, a historic photo archive, not just for the often awesome large-format scans but even more so for the flippant titles, sarcastic captions and insightful comments (like the post's title, which captioned this image.

Or photos like the earliest pig photobomb, or the feeding time sign, or the subwoofer photo...the list of goodies is endless. There's also a large amount of great but very bleak photos by people like Lewis Hine or Dorothea Lange.

Browsing shorpy is great but wastes time like nothing else (except maybe wookiepedia).