You'll likely never need to neutralize supercriminals in an overrun insane asylum, but with the guidance of an Instructable by user Spookylean, you can craft a (semi) working "Batman: Arkham Asylum" style batarang just in case. You don't even need Bruce Wayne's limitless budget either, just around $20, some tools, ten hours and some good old fashioned Bat elbow grease.Spookylean's recipe calls for plexiglass rather than metal or wood for the sake of a lightweight and easy to render batarang replica. It seems like a pretty ideal item for cosplayers since it focuses on aesthetics and basic functionality rather than literal boomerang utility, although hardcore would-be crimefighters can probably adapt the instructions to more solid materials.

Check out the batarang action below to see its unfolding action:

[Via Greatwhitesnark via Makezine via Instructables]