Yes - This is what I was thinking..
Aside from the technical difficulties, could you regulate the Money Supply if you knew the Price Of Gold, in the currency ?
Or - Which I can see a way of doing, could you regulate the Money Supply if you knew the Price of a Bitcoin .. ?
So that, if the Price of Gold/Bitcoins went up, you would print less..
If the Price of Gold went down, you would print more.
I think this is known as the 'Gold Price Rule'.
http://www.forbes.com/sites/steveforbes/2013/05/08/heres-what-a-new-gold-standard-could-look-like/
I think the Freicoin altcoin is one of the only ones out there that comes close to what you're planning but that hasn't been a great success and because I follow a different economics school I'm just being smug about that and saying it's because of the kind of ideas you're talking about in the first place but again I welcome currency competition, it's just the critics of deflationary currencies that don't. Oh yes! I almost forgot infinite coin, that's an inflationary currency someone made too, it's not doing too great either, there's also stuff like Starcoin and Luckycoin which give out random rewards, so there's all kinds of experiments happening.
Don't worry - no one is talking about 'wrecking' lovely bitcoin.. This would definitely be an Alt-Coin.
Just trying some different ideas out. Thinking out loud.. So many possibilities now that were not even thought possible BBTC.. (before bitcoin.. ;-p)
As I said in the OP, if you could take the Human element out of the equation, maybe some of this stuff is not soooo terrible..