One thing I find interesting about the criminal angle of bitcoin is that all the transactions are traceable. You can look up any given address and see exactly what they've been doing with their coins. The addresses may be anonymous but any law enforcement agency that was looking into bitcoin transactions would be able to put names to those addresses over time.

I'm actually surprised that more countries haven't been looking at cryptocurrency as an avenue to update and modernize their currencies. Would be some major hurdles to deal with in that process but you'd be able to improve things long term.