The most over-packaged device that I bought recently was a pair of Razer HD-1 5.1 channel headphones. In my haste to extract my hard earned gaming booty, I lacerated my finger in a fairly nasty but minor way. It hurt as it did the time before and the time before that. Open It is a purpose built tool for preventing exactly the kind of mishaps that I just mentioned. It features some powerful looking steel jaws, a retractable utility blade and a screwdriver. That should be everything you need for tearing into every type of package known to man.
Price: $12 from Amazon