I have heard of them (someone used to post about them on here) but don't really know what they 'do'
Wish I'd bought a couple of dollars worth when they came out though
My understanding of bitcoins is very limited but I think part of the answer to your question, mikey, is that (see Wikipedia article) some merchants such as Paypal, Expedia and Microsoft do accept them
This might be the point at which real governments who have been inconvenience by this hack (which, like all others, is only profitable because of these artificial cryptocurrencies) gather their collective nerve and declare bitcoins and their nefarious siblings to be 'non-negotiable' for real money.
The whole vile, crime facilitating, farrago could be stopped if the collective will exists.