Hand-Held Shredder

The Ziszor is a nice little battery-powered, hand-held shredder.

Great for shredding small items like credit card statements, so the dumpster divers have a bit more trouble stealing your identity.

Perhaps a hand-held furnace would be even more effective, but you wouldn't want to contribute to global warming.

As Popgadget suggested, the best use for it might be to attach one to your letterbox by a string and ask the mailman to just shred any junk mail for you :-).