What's behind all this insane movement?
Insane levels of greed and fear is the short answer.

Normal markets don't have people all over the internet talking about how much money they made (i.e The thread where someone bought in at $5 and now they have a new $30,000 vehicle), and/or how certain they are that prices are going much higher.
Then add people borrowing money to "invest", and you are set up for huge price moves.