Rifftraxs are .mp3's that you sync with a DVD which provide a hilarious MST3K-esque commentary. It was created and is performed by Mike Nelson of MST3K fame, though occasionally guest riffers with stop by to help, such as Kevin Murphy (also of MST3K fame) in the Star Trek V riff.

"It sucks that MST3K got cancelled, huh?" says Uninformed Yet Impressionable Friend
"DUDE! YOU GOTTA CHECK OUT RIFFTRAX! IT'S JUST LIKE MST3K, EXCEPT NOW HE MAKES FUN OF HOLLYWOOD MOVIES!" replies Hyped Up Rifftrax Fan.
by Mike August 23, 2006
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