Worth Your Weight in Gold – Link
Evil Mad Scientist has fun analysis of this question for all kinds of materials from different forms of money (dimes = quarters by weight) to flour and culminating in antimatter (BTW, very valuable by weight!). EMS gives the question a few entertaining twists. Here is an excerpt:
Kopi Luwak coffee costs approximately the same amount per pound as human blood. (Knowing where it comes from, I think I’d rather drink the blood. It’s been pointed out before that printer ink is also up there, but I’d rather not drink that either.)
Would you have guessed that peacock feathers can be worth more than their weight in dollar bills? Or that a fancy steak costs twice as much as its weight in dollar coins?