My top 10 are ( in no order)

Neon genesis evangelion
Fruits Basket
Yu-gi-oh (original series+season zero)
Case closed (detective conan)
Slayers OVA series
Pani poni dash
Elfen lied
Sprited away
Noir
Excel Saga

Least 5 (in no order)

Madlax
Avenger

( I can't think of anymore because most animes i enjoy alot)
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Forgot to add to my least 5

FLCL
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Forgot to add to my least 5

FLCL
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sorry for double posting