What if someone had a photoblog 100 years ago? That's the neat idea behind Shorpy, where a time machine meets the internet.

They don't take the conceit to extremes: there's no attempt to reproduce the more florid style of yore. And it bends the rules a bit, as time machines are allowed to do, by jumping around chronologically (geographically, too).

What you get, though, are fabulous, mostly black-and-white images, glimpses of other times and other places that seem to jump thrillingly back to life.