The most cloned bands in history...
 

Straight away this comes to mind...

http://image.allmusic.com/00/amg/cov...664131f386.jpg

Followers (source AMG):
Midget . Big Rig . Los Lagartos . Longfellow . Zebrahead . Cleveland Bound Death Sentence . Room Full of Walters . Bueno . The Movielife . Brave Saint Saturn . Junction 18 . Tsunami Bomb . Enemigos de la Klase . Stolen Thought . Cauterize

And 1,000 others a week.:(

I don't know about this band, but I know they've tried harder than any band I've known of.

Socialburn.

They sound almost exactly like Nirvana, the same exact style, and they even have a singer that kind of sounds like Kurt Cobain. Not a coincidence.

http://image.allmusic.com/00/amg/cov...01826y5n7e.jpg

So that's the obvious two out of the way...

Korn defenetly.

Even though there are some nu-metal acts that I like (KoRn, limpbizkit), I have to admit it seems more like they all copy off of each other... ;)

I think there are alot of bands that also try to copy the catchy music that the Ramones made...

Black Sabbath

Followers: Anthrax Cannibal Corpse Megadeth Motörhead Henry Rollins Sleep Spinal Tap Fonya Jim Martin Karma to Burn Spider Virus Bliss Peach The Black League Pleasure Forever Jumbo's Killcrane Thyrfing

Spawned a large genre and every nu-metal band and thier grandma claims to be influenced by them.

Yup, most modern punk bands do copy them. Very few can at least say that they sound just as good.

Hmm... My favorite punk bands are Tsunami Bomb (already mentioned as green day imitators above), Bad Religion, and Pennywise. At least for mainstream shit. I'm fairly good at somehow missing classic bands so who do they copy?

The classic bands just did 'something different'.

The Jesus & Mary Chain
http://image.allmusic.com/00/amg/pic...07766u12o1.jpg

AMG
'In late 1984, the band issued its seminal debut single, "Upside Down," a remarkable blast of livewire feedback anchored by a caveman-like drumbeat; the record made the Mary Chain an overnight sensation in the U.K., as did their nascent live shows, 20-minute sets of confrontational noise (performed with the band's members backs to the audience) which frequently ended in rioting.'

Too many followers to list.

To put things in short: Black Sabbath was THE first "metal" band... :)

And I would almost say Megadeth copied Metallica to a certain extent, seeing as Dave Mustaine was a former member before he was replaced by Kirk Hammett before their first album "Kill 'Em All" was released...