Anti-insect laser gun turrets designed by Osaka University

Nathan Myrvold demo'd this at TED 2010. https://www.youtube.com/watch?v=fwyMuwNYKvI

Safety is a blocking issue last I heard - something powerful enough to zap a bug can also permanently blind a retina.

David Brin came up with this idea in his 1990 novel Earth, where the "bee zapper" was used against africanized (aka "killer") bees.