The Canadian $1 million coin weighs approximately 220 pounds, most of which is comprised of gold bullion, and sells for roughly twice its face value due to the high value of its content. Don't plan on paying for sundry items with this. You'll empty the vendor's till and everything in the bank.

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We often think of money as a means of exchange in paper and rounded metal form with conventional denominations. Think again. In the long history of currency, forms of payment that would appear stranger than fiction have appeared. Indeed, before the advent of money, barter was the accepted means of payment where anything could serve as "currency." Here's a brief tour through the quirkier side of the medium's history. Funny money, indeed.