Iron Maiden (2003) - First got me into music that I didn't passively consume via the radio, period.
Blind Guardian (2004) - First got me digging a little deeper for bands.
Genesis (2004) - Kicked off my love affair with challenging music, and with my anglophilia.
Mastodon (2004) - Leviathan was my first "new album" that I loved, before that I had been digging for classics.
At the Gates (2004) - Got me into death metal.
Immortal (2005) - Got me into black metal.
The Decemberists (2006) - Got me into non-metal/prog rock, can't defend all their stuff today but I wouldn't be in the indie rock biz without 'em.
Mouth of the Architect (2006) - Made me give a shit about local shows and "the scene," for whatever that's worth. I've fallen out of touch with the scene here (because there aren't good bands in it) but going to shows in sweltering basements and makeshift galleries in Dayton, Ohio from 2006-2009 will always feel like home.
Wolves in the Throne Room (2007) - Got me into "criticky metal" which is mostly what I listen to today.
Fucked Up (2011) - First band that as an on-my-own, independent adult that really resonated with me. I've traveled all over the world to see them and I'll probably always associate them with that transition from a kid to a man. (I turn 23 this year.)
Mortals are mortar and life is the fuse.