So in lots of threads there has been discussion about forking the block chain because of various reasons, such as the fact that early adopters of the system got lots of coins practically for free. In this thread I don't want to discuss if forking the chain is OK, but about ways how the chain could be forked. If you just want to argue against forking please go to another thread.
The typically mentioned way to fork is a "full fork": You just use a completely new block chain that works in parallel to the original block chain. Personally I don't think that this is a good idea or that such a fork will be successful: If there's only a slow adoption of the forked currency you just replace the original group of users that got lots of Bitcoins with cheap mining with a new group of users that will get lots of forked-Bitcoins with cheap mining. In addition, it's easy to attack a forked block chain if you can mine coins fast enough. I wouldn't be suprised if in the case of a forked chain some of the original Bitcoin miners would form a "Bitcoin cartel" that computationally attacks all forks in order to protect their own wealth (in Bitcoins).
Instead, I have another suggestion for forking the chain: Why create a new chain when you can just reuse the original chain? For example, let's just say that all coins generated before block X have zero value to you and your group of friends and that you just use "new coins" for trading. It would be possible to provide such a feature in a forked Bitcoin client by separately displaying old and new coins. If your group of friends is large enough this will mean that "new coins" are more expensive than "old coins" because there is slightly more demand for new coins.
This would give two options to existing Bitcoin users: Either they adapt to the "new coin" system and thereby increase the price difference between old coins and new coins. Or they ignore the new coins, but thereby allow others to make money using the arbitrage between the two different coin prices. Clearly, the second option is not a rational decision for each single individual: Why would you treat you new coins the same as your old coins, when you are able to charge a higher price for your new coins?
Maybe this whole approach could be somewhat more generalized by introducing a "demurrage" [see http://en.wikipedia.org/wiki/Demurrage_(currency)
] for the ownership of Bitcoins. For example, by defining that each coin looses 10% of its value in each X blocks (or Y years) and by having a "new type" of Bitcoin client that transparently does this calculation for you (shouldn't be too hard to implement, as the total balance is the sum of the coins - and those coins are known to the client). The advantage of this demurrage would be that it makes speculation less attractive, and that it somewhat decreases the problem of peoplewho now hoard tons of Bitcoins that they've mined pratically for free.
Any other ideas to fork the chain? Which of those ways do you think would be most successful?
Again - my plan is not to fork the chain, neither I'd like to discuss if forking is a good or a bad think. At the current point I'm just interested in the theoretical aspects: What is the most promising method for a fork? How likely is it to succeed? etc.