Bloodbath
https://www.youtube.com/watch?v=UBfoMgllphs
Be'lakor (A song I'd like to have played at my funeral)
http://www.youtube.com/watch?v=yY625tkzs2E
Viatrophy (Made my ringtone from this song)
http://www.youtube.com/watch?v=n4aCmNOjL9k
Arsis (dat solo @ 1:38)
https://www.youtube.com/watch?v=WA2HVDA2OAA
Born of Osiris
https://www.youtube.com/watch?v=H2Fkt3JkJbk
Brain Drill (Not quite my thing but still worth a mention)
https://www.youtube.com/watch?v=wEywYigygnk
Carnifex
https://www.youtube.com/watch?v=TNxnXnBZ4cw
Cerebral Bore (Yes that's a chick singing, she could have my babies.)
https://www.youtube.com/watch?v=gWE9YmB8reQ
Dagon
https://www.youtube.com/watch?v=aBkmK6YNzlo
Decapitated
https://www.youtube.com/watch?v=-KFObx3n2K0
DevilDriver
https://www.youtube.com/watch?v=AWKppF-ZcBI
Devourment
https://www.youtube.com/watch?v=lpkjLHtylu0
Dying Fetus
https://www.youtube.com/watch?v=QVJxCLcU6Wc
Fractal Gates
https://www.youtube.com/watch?v=QbJW2N_yevU
Gojira (Metal you can trip to)
https://www.youtube.com/watch?v=Ua0rpM9nKjI
https://www.youtube.com/watch?v=Qqg8bsDayak
Gorilla Zoe (Had to make sure you were paying attention, it's a good song though. "Back in 5th grade I used to wear bobo" true story)
https://www.youtube.com/watch?v=Dtqh0dhEKZk
Hate (A classic band from Poland)
http://www.youtube.com/watch?v=8-6VyYrMnlw
I Declare War
http://www.youtube.com/watch?v=o3zfLrD4RdA
In The Midst of Lions (Christian metal band, don't agree with religion but it's good music.)
http://www.youtube.com/watch?v=R1PD8A-ll6w
Ingested (A nice transition from the previous christian band, ha.)
http://www.youtube.com/watch?v=HUkw-fGnMuc
Kittie (My childhood crush)
http://www.youtube.com/watch?v=j2-5VAmOAz8
Kreator (Another classic band)
http://www.youtube.com/watch?v=dR7xBj0bDD8
Lamb of God (This song is how real men live life.)
http://www.youtube.com/watch?v=6sIzP_81v6g
Living Sacrifice (Another christian metal band, hey if it's good music fuck it.)
http://www.youtube.com/watch?v=ENOdrve_2Uk
Lords of Acid (Just making sure you're still paying attention, they are badass though.)
http://www.youtube.com/watch?v=o5zZthqTr-4
Machinae Supremacy (This is what happens when you mix metal and video game music, just avoid their songs with singing imo.)
http://www.youtube.com/watch?v=yKC2bpyGMgg
MadHatter (This is what happens when you mix rap and video game music... it had to be posted.)
https://www.youtube.com/watch?v=i1el0PFwJAI
Månegarm (Back to some real metal)
http://www.youtube.com/watch?v=Y9J_PV7OyAw
Molotov Solution
http://www.youtube.com/watch?v=Hmv6TMaCKCM
Mudvayne (Surprised they weren't already mentioned)
http://www.youtube.com/watch?v=9nVvojfQVBY
Nightrage
http://www.youtube.com/watch?v=f-rHbDL7Ra8
Nightwish (This is what happens when you mix LotR and metal... fuck you...)
http://www.youtube.com/watch?v=rZtF5-SMh7g
Noctem (...back to real metal)
http://www.youtube.com/watch?v=RlD9TRjKgRs
Norther
http://www.youtube.com/watch?v=cOB5pkbQLZ0
Obsurca
http://www.youtube.com/watch?v=mesr2siegRg
Oceano (Is that a black guy singing? Why yes it is, now we've seen everything. You're welcome)
http://www.youtube.com/watch?v=aGS8vvQKg14
Orgy (This is what would happen if Freddie Mercury from Queen made a 'metal' band)
http://www.youtube.com/watch?v=UB7CbOhH0Wo
Seriously though this band would be my guilty pleasure
https://www.youtube.com/watch?v=iTRLyso4SA0
Revocation (Back to some real metal)
http://www.youtube.com/watch?v=1kRZ1YG5ugY
Rings of Saturn (Good luck listening to this)
http://www.youtube.com/watch?v=ZgtUHHk30uc
Rose Funeral
http://www.youtube.com/watch?v=qnHb-ioJ1oI
Salt the Wound
https://www.youtube.com/watch?v=CMs9yNlBp4c
Skyfire (What happens when Sonic the Hedgehog music mixes with metal, jk... not really my kind of band but someone might like it)
http://www.youtube.com/watch?v=N1zMxuIeTiI
Sonata Arctica (Another variation of metal, not really my thing but worth mentioning)
http://www.youtube.com/watch?v=iy81-mzwQoE
Suffokate
http://www.youtube.com/watch?v=g1omwOq7eiE
Swashbuckle (Pirate metal... ok now you've seen everything.)
http://www.youtube.com/watch?v=0XAzRrXtgto
The Faceless
http://www.youtube.com/watch?v=k2UNXm_2yH0
Fleshgod Apocalypse
http://www.youtube.com/watch?v=sRXbEt0otHg
Suffocation
http://www.youtube.com/watch?v=i6nrglujp1U
Few Against Many
http://www.youtube.com/watch?v=hAgXcjGOhb8
Tracedawn (a WTF video, but an awesome song and band)
http://www.youtube.com/watch?v=N3MdcYhRPps
Tristania (...Probably not for you, but they are creative and well thought out imo)
http://www.youtube.com/watch?v=duST2l6c0sQ
Vader (Another classic metal band)
http://www.youtube.com/watch?v=raerE_zUfCA
Viraemia (Like BrainDrill and Rings of Saturn... good luck to your ears)
http://www.youtube.com/watch?v=nZHa-ixQSrw
Warmen
http://www.youtube.com/watch?v=kF05bqo6ZZU
Winds of Plague
http://www.youtube.com/watch?v=-MrIzF8TQ30
Wintersun (An amazing band)
http://www.youtube.com/watch?v=B6px4BLVtdg
Witchery (Another classic metal band)
http://www.youtube.com/watch?v=z88mSch_fwc
Finntroll
http://www.youtube.com/watch?v=yGywo81G6lk
Winds (Classy metal and one of my favorite artists of all time)
http://www.youtube.com/watch?v=4K7TA2qvEFQ
Last but not least Amon Amarth (I only bring this band back up because the link provided by Taker is broken and this band is awesome)
http://www.youtube.com/watch?v=ZPRt6Tt6RyM
I have more metal bands but I doubt anyone will go through this entire list as it is... but at least this thread is a bit more complete. Enjoy