This article comes via Wired.com, and reports on the Monolithic Bee project at Harvard University, where they have found an ingenious way to construct small scales bio-mimetic robots. It doesn’t actually show them flying or swarming, but it’s damn fine work nonetheless.
From Wired:
Harvard University engineers have come up with a production technique inspired by pop-up books and origami, that allows clones of tiny robots to be mass-produced in sheets.
Pratheev Sreetharan and colleagues at the Harvard Microrobotics Laboratory have been working on bio-inspired robots that are about the same size as a bee, can fly and can work autonomously as a robotic colony.

http://www.wired.com/wiredenterprise/2012/02/robotic-bee/
More information direct from Harvard: http://www.seas.harvard.edu/news-events/press-releases/pop-up-flying-robots