"if nothing is forever, can I be your nothing?"
A gift that lasts forever is a great gift indeed (Humor included). Imagine the laughs you get from this gift.
What exactly is it?
Nothing is packaged like a toy (an Ideal gift).
Now when a special occasion that constitutes the giving of a gift comes up and you ask "what should I get you?" and they say "aww, nothing would be fine." take it literally!
This falls under the category of greeting cards to me.
$6 + shipping for nothing (maybe a laugh or two).