Metal rubber band guns from Japan. Looks pretty cool. It’s probably cheaper and easier to make a lego rubber band guns though, but they obviously wouldn’t look or be as cool.
http://gigazine.net/index.php?/news/comments/20100207_wf2010_w_kerberos/
http://gigazine.net/index.php?/news/comments/20090726_wf2009_s_silverwolf/
