Churdtzu, Thank you for this reply! I think the form a government crackdown would take would probably be selective prosecutions. Govmts could simply start prosecuting large numbers of people involved in alt currency for crimes such as tax evasion. This is not to say that alt currency users are breaking the law more than others, it's just that every individual and business is subject to so many rules, and it's not uncommon for govmts to selectively enforce these rules towards particular ends.