Bands that blew your mind...

Sepultura - Got into extreme heavy metal from listening to "Roots Bloody Roots" and "Chaos A.D". I was 16 at the time and it seemed pretty extreme to me but I loved it.

Bolt Thrower - Around 17 or so I started looking into some death metal after listening to some Obituray and Bolt Thrower impressed me right off the bat.

Entombed - Again around 17 or so I downloaded "Left Hand Path" and I was into it just like that.

Obituary - They were the very first death metal band I ever got into when I was 16. I was listening to this metal show on the radio and I was totally mesmerized by that song of theirs on Slowly We Rot "'Til Death".

Pantera - Early 2002, I bought Reinventing The Steel and I started digging them then I bought all their albums. Good times :D
 
mindblowing were my first tastes in real metal... it was Slayer - Divine Intervention and reign in blood 2 days later... the awesome fury on DI made me buy RIB and I was getting multiple orgasms listening to both in the begining... hahah now still with RIB...


you know what I mean! hehe
 
metallica- and justice for all. when i was like 10 i got into gnr, skid row, poison, etc etc (i still like those bands, by the way) but when i was about 12 a friend of mine showed me justice and i was amazed at how angry music could be. i listened to a dubbed copy of justice about a million times, then bought their other 3 respectable releases, along with megadeth, anthrax, slayer, etc.

faith no more- the real thing was the soundtrack to 7th grade. i idolized mike patton like no other.

alice cooper- i was first exposed to alice cooper through megadeth. i heard their no more mr nice guy cover and thought it ruled. then i heard the song "poison," and bought trash. i now own 25 or so alice cooper albums and i think he is the most brilliant man to ever exist.

bands that have killed me fairly recently (recent comparitively at least):
-iced earth- in '99 after something wicked came out, i didnt know who iced earth was and i randomly went to see them at a club here, and i was blown away. have since accquired all of their records and they reside in my top 5 bands ever.
-hammerfall- first power metal i ever heard. i love the shit out of this band.
-exhorder- never heard of them when they were around, but bought the 2-in-1 on a strong reccommendation, and i love it.
 
Albums are timeless, bands are not. I'll list some albums that 'blew' my mind when I first experienced them.

Blut aus Nord - Memoria Vertusta
Blut Aus Nord - The Work Which Transforms God
Beherit - Drawing Down The Moon
Moonblood - Blut Und Krieg
Graveland - Thousand Swords
Graveland - Creed of Iron
Graveland - Immortal Pride
Nokturnal Mortum - Goat Horns
Darkthrone - Transilvanian Hunger
Demilich - Nespithe
Demigod - Slumber of Sullen Eyes
Burzum - Filosofem
Unanimated - Ancient God of Evil
Deathspell Omega - Si Monvmentvm Reqvires Circvmspice.
Clandestine Blaze/Deathspell Omega split album
Nocturnus - The Key
Dissection - The Somberlain
Destroyer 666 - Cold Steel... for an iron age
 
Blind Guardian
was the first real metal i listened to - great stuff

Burzum
First i was bored by it - then it grew on me very slowly for some time... and in the end i listened to it one time and it .... blew my mind..

Nargaroth
This intense atmosphere... it took only oine listen

Gorguts
I borrowed an album by a friend... Obscura - i can't yet make out, what exactly is going on, but it's complexity has a great fascination on me

Ulver(Black metal era)
Just a great forest atmosphere i love...
 
The Good ole days:

METALLICA
ACCEPT
WASP
MAIDEN
TESTEMENT
SLAYER
S.O.D
ANTHRAX
KING DIAMOND
MORTAL SIN
MEGADETH

The Last Few Years:

OPETH
Katatonia
SYSTEM OF A DOWN

From a prog point of view, OPETH are by far the best metal band in history, bringing beauty and brutallity to a new level.