A Seattle, Washington man who was tired of packages being stolen from his front porch, has come up with his own anti-theft device.Jaireme Barrow calls it the Blank Box.It's an empty box, made to look like a package, but it's rigged with fishing wire and a 12-gauge shotgun blank that goes off when the box is lifted.From surveillance video, it seems to work. Would be package thieves have been sent running by the loud bang.A warning though if you're thinking about making your own device - If you rig a package like this, and it injures a thief, you could be held liable.Police say your best bet is to file a police report and hand your surveillance video over to investigators.