*** Oct 2011 Update ***
If you're into Arkham Asylum or Arkham City props, check out a build I'm working on right now, Batmans Grapple Gun.
Grapple Gun Build
*** End update ***
I kinda got a bug up in me lately about Batman weapons, so I did a little huting around and found one of these on ebay:
This was part of the "deluxe" packaging for the Batman Arkham Asylum video game. While I don't play video games, I did think this was a pretty cool interpretation of the batarang.
While not the highest quality of pieces, I find it quite nice. It's injection molded plastic, and has a weird faux scratch surface, I assume to resemble battle damage.