Steel Panther vocalist Michael Starr joined The Darkness on stage at Hellfest to help the band perform their classic "I Believe In A Thing Called Love." Which if you were alive when that song dropped in 2003, was completely inescapable. Starr and the The Darkness did a great job, though given the talents of both I'm not sure that's surprising.
Steel Panther's own set at Hellfest also made headlines recently when the band covered Ozzy Osbourne's "Crazy Train" with Starr dressing as the man himself and biting the head off a fake bat. You can check that out here.