So I don't devour ye ol' anime as much as I used to but I still have a love for it!
Favourites would have to be:
Ergo Proxy (Overall favourite - love the dark animation style and physiological aspects)
Noien (For concept)
Claymore (For fights/story)
5 Centimeters per Second (For animation/story because I do admit I love my slice of life! - I must mention my love of the animation in Time of Eve though!)