Enter Sandman, Paranoid, etc.

Tokai Les Paul LS65
Carvin MTS3200 212 Combo
Boss SD-1 with Monte Allums GT Mod
Dunlop Crybaby

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Epi Les Paul Std w/Duncans
Cry Baby From Hell
Marshall JH-1
EHX Metal Muff
MXR EVH Phase 90
Carl Martin Classic Chorus
EHX #1 Echo
Ibanez LU-20
Dunlop DCB-10
Crate V50112
Tascam US144

Seeing as how metal is one of the hardest genres to play...there isn't a whole lot out there...

Depends on what you consider metal though as well; because you could be talking about:

Pop, or fake metal, i.e. Slipknot

Old school metal, i.e. Zepplin or Maiden

Real Metal, i.e. anything from Scandinavia and or Europe in general

So give more information, although the intro to Ozzy's "Crazy Train" isn't too difficult, and your friends would probably recognize it...