Of course, governments always want more. It seems to be the main goal of politicians, to think about new places to collect taxes. If the government can take cryptocurrencies in some way, of course the will! I guess it may best fit under capital gains or income tax. I feel like it would be very hard for the government to trace though, unless you are converting it to fiat currencies in your own country. Could the government actually track and tax your cryptocurrency? You don't have your name and DOB attached to it, do you?