What are the greatest Growth Hack stories of all time?

There's a lot of growth hack stories out there (everybody know the classic examples with Dropbox or hotmail), but I think a great growth hack story is all about the overall journey and not necessarily one big boost that help the business get there(anyway IMO, growth hacking is about a bunch of small experiments rather than one big hit. That's why I think this source is great to show you a bunch of growth studies: https://growthhackers.com/growth...