The act of getting your YouTube video tweeted out by a media outlet/celebrity (such as James Gunn) which then causes a chain reaction of increased popularity. The increased popularity of the video results in increased advertisement revenue for the creator, hence the dollar sign. However, the root of the term comes as a play-on-words for the Fergie song "M.I.L.F. $".
What happens when you’re so ridiculously bored that you pick up a mobile phone and type everything into the Urban Dictionary to see if something comes up and don’t realize that you had .,?!’ in there twice.
Person 1: I’m so bored I’m just going to type qwertyuiopasdfghjklzxcvbnm1234567890-/:;()$&@“.,?!’{}#%^*+=_\|~<>€£¥•.,?!’ into the Urban Dictionary.
Person 2: I think you repeated .,?!’