Everyone has seen these - fused plastic packaging containers for small products, such as CompactFlash cards - my most recent experience has been with an iPod case. These packages are pretty much impossible to open without a knife or industrial-strength scissors, and of course those often aren't available.

It's especially bad for packaged small multiple items - by the time you finally rip the package open, the amount of force that is being applied sends contents all over the room, quite often never to be seen again.