I didn't include live albums in my initial list, but if I did, I'd include the following:
Iron Maiden--Live after Death
Ozzy Osbourne & Randy Rhodes--Tribute
Dream Theater--Live at Luna Park
Iced Earth--Alive in Athens
Rush--R40
Slayer--Decade of Aggression (especially the first CD, recorded on the Clash of Titans tour in 1991)
Dirkschneider--Back to the Roots
UFO--Strangers in the Night
And a few more studio albums I thought of since I started this thread:
Savatage--Gutter Ballet: I thought about Streets, but it drags a bit in the second half. However, Gutter Ballet is a perfect album, where every song is just plain awesome, especially Of Rage & War, Silk & Steel and Unholy
Virgin Steele---Marriage of Heaven & Hell Part 2: Although I like some of the albums that follow this one more, I can't deny that song-for-song, this is a truly excellent album, particularly in the fast-paced opener Symphony of Steele and the epic Emilaith
Type O Negative--Bloody Kisses (Digipack Edition): This is a truly awesome album, with a near-perfect atmospheric sound, especially in the epics Christian Woman and Black No. 1. The reason I choose the digipack edition over the regular edition is that it has an excellent inclusion in Suspended in Dusk.
Pantera--Vulgar Display of Power: This band served as a perfect bridge between the old-school thrash of the 80's and the metalcore sound of the 2000's. I've heard the term "groove metal" to describe them, and it works, especially on songs like Mouth for War, Fucking Hostile and This Love.
Exodus--Tempo of the Damned: Many classic thrash metal bands have struggled to find their sound from the late 80's or early 90's, but in 2004, Exodus got it right, with one of the most aggressive albums. The (brief) return of Steve Souza really gave them a kick in the ass, and they did so perfectly. The lyrics in particular are every bit as brutal and uncompromising as they were in their prime, while the thrash was as good as it ever was, especially in songs like Scar Spangled Banner, Blacklist and Forward March.
White Zombie--Astrocreep 2000: This wound up being the band's final album, and what a way to go out. Although "More Human than Human" got the most attention, this album is chock full of excellent songs. My favs are "Electric Head Part 2," "Real Solution # 9" and "Blood Milk and Sky."