Lloyd, thanks for your comments. I agree that the countless number of cryptocurrencies in existence all have their own nuances. However, the underlying point that none of them have sovereign backing or recognised as legal tender pertains to all of them. The housing bubble in 2008 was more a function of over enthusiastic lending practices by the banks facilitated by the rating agencies. The dot.com bubble crashed when it became apparent that overly optimistic investor expectations for these new technology companies was going to miss reality by a substantial margin.

On A rolling bubble gathers no moss -