The first half of the headline is the title of an upcoming episode of the Simpsons.*
Based on 20.8 million shares of Solar City, down $3.77 (5.84%) and 33.1 million shares/options of Tesla, down $9.29 (3.58%) Elon is off $78.40 + $307.50=$385.9 million on the day.
*According to the Simpsons Wiki "The Musk Who Fell To Earth" will air on January 11, 2015.
SynopsisScript copyright applied for.
Mr. Burns will lose all his money to Elon Musk. Mr. Burns will try to kill him, and it will reveal Elon Musk's master password.
(why? it's copyright when written)