I am imagining wallet where you can add and remove coin/material types from a drop down menu, providing the balance on hand is 0. You will have all of the common scrap yard material. Aluminum, Steel, Copper, 316 Stainless, Car Batteries etc as different coins. (colored coins?). Each coin type will have a set price, which automatically updates based on the world markets. Eg. Copper - $1.00 USD(lb) Cast Iron $0.62(lb) Gold $1028(oz)
There are three ways you could set this up...
1st option - This is going to be difficult but it would be awesome. In order to introduce coins/material you would need to mine the scrap, this wouldn't be mining, it would be "picking"
In order to pick certain materials you could add an option to the miner such as -C to mine copper, or -G to mine gold. The network would pull the current price of all scrap material from somewhere on the internet and base the difficulty to mine the corresponding material on that. Thus, cast iron would have a low difficulty, to mine aluminum would be a medium difficulty, and to mine gold or platinum would be a very very high difficulty. The neat part about this is, low priced scrap would be easy to find and rare scrap like tungsten would be very difficult to find but have a much higher value. Similar to the penny, nickel, dime, quarter, loonie etc. It would be like 20 different coin types within one currency. I am trying to wrap my head around how the set price of a colored coin, would hinder/promote mining. Imagine if bitcoin had 20 different difficulties of colored coins with set prices. What would happen? I think the miners would go after the "low hanging fruit" so to speak which would self regulate. If too many miners tried to mine copper it would no longer be practical. However, once the hashrate came back down to earth it would be economically feasible again which would keep the network alive and not waste excess power from insane difficulty levels.
2nd Option - Same as above, but instead of mining a certain coin/material type you simply mine "scrap" If you find a block that contains 50 coins, well lets call it a "truck load" it gives you an assortment of material types and quantities. You never know what you will get. Now that i think of it, it would be kind of like minecraft. (random) I am not sure if this would be a regulated value per truck load or if it would be completely random based on the rarity of the material. (You would never end up with a bunch of platinum, more like a couple car batterys, a radiator, 182lbs of cast iron, and a 6 lbs of copper)
3rd option - The material types are interchangeable, and while mining it would simply generate "scrap" Once the scrap lands in your wallet you can divide it however you like. If a block gives you 50lbs of "scrap" worth $24 you can leave it in your wallet as 50lbs of scrap, or you can divide it out. 50lbs ($24 USD) of scrap can become 4.0 copper, at $1.22(lb), 1.5 car battery at $9.50(ea), and .0001 silver worth $4.87(oz) = $24 Because each material type fluctuates based on the average market value across the world, you could move your scrap in and out of any material type you wish to speculate or hedge against swings in price. The price of "scrap" is simply the averaged amount of all the materials. It should also be a side chain to BTC so if i sell 8 car batteries to Jim, and he pays me by sending 8 car batteries in BTR, i can immediately convert it back to scrap, copper, lead, silver, or BTC if i wanted to spend it.
One thing i cant figure out is if there are 20 different coin types as per the first example, how you can distribute the coins in the first place? These coins are essentially tied to the real life scrap markets and can not be pumped. Well, i guess if they end up on an exchange they can, which would create an artificially inflated scrap market. Would someone pay $40 for a car battery that they can only convert to $9.50 worth of BTC?
For an IPO you could take all of the coin types you are going to have in your wallet, along with the current prices per unit of measure, and average a price out, and sell it based on that price. eg:
Gold $1000(oz)
Cast Iron $0.15(lb)
Copper $1.22(lb)
Car Battery $8.02(ea)
Lead $4.52(lb)
Tungsten Carbide $49.52(oz)
Average Scrap Price $176.485/"truck load"
Once you have your price per truck load you could have an IPO where users send corresponding BTC payments to an address. In this case, it would be $176.485 per truck load, and they would sign the message with their BTR wallet address. Once confirmed they would receive an assortment of random material back into their BTR wallet totaling $176.485 of value (at that moments current market prices)
I am not sure if colored coins with a fixed USD value (to world scrap market) and thus varying BTC value, could be in a side chain. It would need to be converted back and forth with BTC to give the scrap dealers an entry/exit to the market.