Heard of it, never used it, because it is too volatile.
The only major use I see is getting around currency controls and buying things in near total privacy. And I hope things don't get so bad in the US that this is necessary via Bitcoin.
Getting your money out of Venezuela or Greece or other nations before a "bail in", absolutely support it as an option. And in such a case, the possible 50% loss of Bitcoin value is worth it when you risk 90% loss to the state.