When you want to congratulate yourself on a job well done and don't mind sounding like a geeky dumbass.

Don't let anyone tell you you're using it wrong, it's not some computer-y thing, it's a statement of your coolness.

Plus it rhymes.
"I just put my pants on the right way, I R Teh Winrar!"
by KittyButt September 29, 2009
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