well, they're my all time favourite band. so. . .
my top album is Times of Grace. make sure you get Grace as well, which is the companion disc by Tribes of Neurot. the discs are meant to be played simultaneously. the experience is mind-blowing to say the least.
ASTNS, Sovereign, TSIB, Enemy of the Sun, and Souls at Zero are all brilliant as well. the ASTNS DVD is amazing, and also has a ToN experiment that is very, very intriguing.
on the topic of ToN, does anyone else here have Adaptation and Survival (the insect project)? it is without a doubt the most disturbing thing i've ever heard in my life (read: it's so fucking cool!)