Well, it might always change. Depends on my mood I guess.

But the most recent one i listened to and from which I was and still am very impressed is "Infernal Decadence" by Spectral Wound.

Check it out if you not already did. They are from Canada and are really awesome.

STÍNY PLAMENŮ - Ve špíně je pravda (2001)

MARDUK - Panzer Division Marduk (1999)

ROOT - Zjevení (1990)

And that's pretty much everything when I'm not counting bands that are not pure blackmetal.

"Thornography" + "Nymphetamine" by Cradle of Filth are my top favorites...8-]] 

I like old school Black Metal, so Venom's first album: "Welcome to Hell" (1981).