Facebook should implement their own Crypto Currency and give 1000 FaceCoins to all Facebook users who have had accounts longer than 10 years.
From that point on, just like Steemit! Facecoin can be added to likes on Posts and Photos and Movies and whatever they come up with next. Facecoin can also be introduced to Instagram.
People can purchase Facecoin using real world money or earn Facecoin from Hourly/Daily Informative and Entertaining Posts.
I'm sure online retailers and services like PayPal and Western Union will accept Facecoin on startup.
They could even have a real world Facebook Credit Card that you could use to transfer Facecoin to real world money.