Cowboy Bebop and FLCL. Might have to check out Porco Rosso and Millennium Actress since the other two series I've seen at the top of that list were definately worth watching. I did try watching Samurai Champloo since it was directed by Shinichirō Watanabe (same director as Cowboy Bebop) and while it was OK, it didn't capture my attention.
Issue 50 "Best Anime Ever"
1. Cowboy Bebop
2. Porco Rosso
3. Millennium Actress
4. FLCL
5. Revolutionary Girl Utena
6. Neon Genesis Evangelion
7. Jin-Roh: The Wolf Brigade
8. Castle of Cagliostro
9. Akira
10. Macross Plus
11. Fullmetal Alchemist
12. Now and Then, Here and There
13. Nausicaa of the Valley of the Wind
14. Ghost in the Shell (movie and TV series)
15. Haibane Renmei
16. Grave of the Fireflies
17. Paranoia Agent
18. Boogiepop Phantom
19. My Neighbour Totoro
20. Gankutsuou
21. Tokyo Godfathers
22. Mobile Police Patlabor: the Movie 2
23. Galaxy Express 999
24. Serial Experiments Lain
25. Princess Tutu
26. Mobile Suit Gundam 0080: War in the Pocket
27. Samurai Champloo
28. Planetes
29. The Place Promised in Our Early Days
30. Samurai X: Trust and Betrayal
31: Gunbuster
32. Princess Mononoke
33. Read or Die!
34. Trigun
35. Excel Saga
36. Night on the Galactic Railroad
37. Fruits Basket
38. Vampire Hunter D: Bloodlust
39. Astro Boy (1960's)
40. Urusei Yatsura
41. Azumanga Daioh
42. Twelve Kingdoms
43. Giant Robo
44. Irresponsible Captain Tylor
45. Fantastic Children
46. Card Captor Sakura
47. Kino's Journey
48. Berserk
49. Saikano
50. Vision of Escaflowne