Two of this year's biggest tours -- Ozzfest and the Area 2 -- are headed by musicians who would never be mistaken for twins separated at birth: Ozzy and Moby. Here's our handy guide to some of the differences between the 36-year-old vegan techno wizard and the 53-year-old foul-mouthed, hard-rocking MTV dad.

	OZZY	MOBY
Aging rocker on the tour	Metal madman Rob Zombie	Space oddity David Bowie
Audience	Balding metalheads, and teenage counterparts	Hipsters with shaved heads, and teenage counterparts
Needed at the concert	Ham to toss at mediocre opening acts	Wraparound sunglasses and shiny clothing
In the pit	Moshing, stray fists, and raging testosterone	Belly rings and lanky blissed-out groovers
Tools of the trade	Power guitars and wailed vocals	Macintosh computers and stacks of LPs
Stance on religion	Sings 'I am not the antichrist'	Devout Christian
On meat	Loves it, including live bats	No animal products in more than a decade
Animal lover?	Once worked in a slaughterhouse	Titled 1996 album ''Animal Rights''
Home turf	Cluttered Beverly Hills mansion, seen on MTV	Spare, stylish loft in NYC's funky Lower East Side
Surprising role model	Put John Lennon's ''Imagine'' on his family's CD	Wore an ''I Love Eminem'' shirt on ''Saturday Night Live''