I used to be a huge SOAD fanboy. No lie, right before it was DT, SOAD had my attention.
I love the debut, Toxicity, Steal This Album!, Mezmerize, and Hypnotize.
All of their unreleased stuff/side work is brilliant, too, such as:
Friik!!
Honey
Cherry
Temper
Storaged
Marmalade
Johnny
Forever
Blue
Patterns (Serj with Iommi)
Shame (SOAD with Wu-Tang)
Dam
Their cover of Snowblind
I may be missing some off the top of my head.
Yep. Favorite songs inlcude Chop Suey!, Aerials (see avatar for the beginning shot of the music video), Innervision, Hypnotize, and Marmalade. I don't listen to them very much at all anymore, though.