Even better examples than the employees at Twitter are startup founders. They start a company and quickly raise 500k at a 2M pre money valuation. Suddenly, they own $1M of a $2.5M company. A millionaire, at least on paper. Not much changes in their lifestyle though. They still can't make a down payment on a house and generally don't drive nice cars. And that's the point of the title "paper millionaire". It doesn't mean much if you can't do anything with it.