Taxi drivers, grandmas etc; necessary but not sufficient for a bubble. There are sustained run ups in assets values that can seem crazy but don't reverse. Cons

Taxi drivers, grandmas etc; necessary but not sufficient for a bubble. There are sustained run ups in assets values that can seem crazy but don't reverse. Consider the bane of my life, london house prices. If bitcoin catches on as a means of exchange, e.g. cash in and out of Iran as is happening to some extent, 1 Billion market cap will seem small.