I know this is definitely mall ninja and gun ricer territory, but I'm thinking about getting a Spike's Tactical fake SD can for my AR.
My upper is coming in and it currently has a flash suppressor and a threaded barrel (both no-nos) and instead of permanently attaching something useless that adds length, I'm thinking about permanently attaching something that doesn't add length.
Watch the video. Adds negligable length, but does add cool/lameness (depending on your mall ninja rating).
Hey, at least its not a pistol bayonet, right? ;D (Kidding!)