Top 5, In no particular order:
Noein
Lain
FLCL
Ghost In The Shell
Fist Of The North Star (comedic value... Oh god, its so bad you can't help but be cracking up)

5 Least Favorate:
Fist Of The North Star (worst anime ever made. Ever. It's bad enough to take the next 4 spaces in this too.)
Fist Of The North Star (again)
Fist Of The North Star (again)
Fist Of The North Star (again)
Fist Of The North Star (again)

Probably could toss in a few more on each, but really... do I care?