Backing bitcoin-like currencies with commodities seems like an insanely bad idea.  It will take everything wrong with systems like speculative investments in oil causing gas prices to go up and give it an alternate anonymous underbelly.  That's insane.  I still don't quite get the logic on how bitcoin can be merged with anything.  I don't get why they would do it or how they would mathematically make it work.  What's wrong with just having one currency to rule them all?  I know, I know, the main 2 problems are the finite number of bitcoins causing crazy pricing and sauron will declare war on middle earth using bitcoins  but neither of those should be a big problem for many years.  And wouldn't it be easier to just somehow expand the bitcoin pool with some sort of parallel block chains instead of 2 separate currencies to confuse the hell out of people and make vandors less inclined to accept them?  Can't someone just develop 10 structurally identical chains running in parallel and sharing info with each other but with the same difficulty ratings at all times?