Tiny globular springtail (Sminthurinus niger)
I found this minuscule springtail on the lid to our recycling can. Frans Janssens, a springtail expert who runs www.collembola.org, was able to identify her as Sminthurinus niger (from a photo of her rump, no less). The first verified record of the species from the Nearctic ecozone.
More shots of her on BugGuide:
http://bugguide.net/node/view/740193