Under Musk’s direction, X.com tried out some radical banking concepts. Customers received a $20 cash card just for signing up to use the service and a $10 card for every person they referred. Musk did away with niggling fees and overdraft penalties. In a very modern twist, X.com also built a person-to-person payment system in which you could send someone money just by plugging their e-mail address into the site. The whole idea was to shift away from slow-moving banks with their mainframes taking days to process payments and to create a kind of agile bank account where you could move money around with a couple of clicks on a mouse or an e-mail. This was revolutionary stuff, and more than 200,000 people bought into it and signed up for X.com within the first couple of months of operation.