I forget which blog I found this link on, but I was almost instantly inspired to try it myself. The less than instant part consisted of taking a picture and posting it here...I think I finished this about a month ago.
I made it entirely out of random broken jewelry and pendants that I had on hand. I just took a short length of chain with relatively large links, and attached two charms on each link (one on each side) with jump rings. I put the largest pieces on the bottom, the smallest on the top, and mixed things up a bit in the middle. That's really all there was to it.
I wear it on a very long chain, and so far have only lost one item off of it, which was promptly returned to me by the bouncer who picked it up, so I'm thinking it carries a bit of good luck with it.