I could not agree more about Bitcoin possibly being very overvalued, and many others digital currencies being extremely undervalued.
The global derivatives markets are worth something like $1.2 quadrillion and that is probably conservative ( and a quadrillion is 1,000,000,000,000,000 )
To say the cryptocurrency markets are in their infancy is reasonable. This isn't 1999 again, but more like 1994.
