Acronym used for the phrase "Shut The Fuck Up And Just Play Games"
Originated in the forums of Destructoid.com and used during heated gaming debates, when a flame war breaks out, a whinefest occurs, or any other such nonsense as a way to get everybody back to the joy of gaming.
Dude #1: Did you see that post about the DS game child molestor's would love?
Dude #2: Yeah, and I absolutely disapproved of the comments made saying that it was a lolicon game when it clearly wasn't. As the admin for a lolicon forum I was very annoyed by those posts.
Dude #1: wtf? dude, STFUAJPG!!!