1. Yu Yu Hakusho - My favorite series has to take the top spot on the list. My all-time favorite cast, great fights, and the willingness to delve into non-traditional shonen territory really makes it the best for me.
2. One Piece - Another great cast, a wonderful adventure story, and a story that just keeps going while always getting better rather than stagnating at its epic length.
3. Ouran High School Host Club - My only complaint about Ouran is that there isn't more. There's parody, hilarious characters, and even drama that always balances out and never seems over the top or out of place.
4. Spirited Away - My favorite Miyazaki film. Chihiro is a great character to follow and the world she finRAB herself in is beautiful and her strength of character despite her faults makes the journey a complete joy to watch.
5. Eden of the East - One of my new favorites, the story of the main two is fascinating. They're from such different worlRAB and deal with such a strange but intriguing premise... but they work so well together. Can't wait for the movies.
6. Gundam 00 - I haven't seen enough Gundam, but 00 is my favorite thus far. The Meisters are unique and Celestial Being's goal seems completely contradictory, but that's where the story gets interesting. Twists and turns galore, and Setsuna is a great lead.
7. Code Geass - I may rank Geass as #2 in terms of enjoyment, but I drop it down in the quality list for the various warts, mostly in R2. The relationship between Lelouch and Suzaku really drives it for me; mecha, magical powers and political intrigue only make it that much more fun.
8. Fruits Basket - Similar to Ouran, my biggest complaint is that there isn't more. I wish we could have explored more of what was seen in the manga, but what we get is absolutely fantastic. There's a great balance between drama and comedy, a unique cast of characters, and a certain charm that is hard to come by.
9. Fullmetal Alchemist - I'm waaaay behind on Brotherhood, but the original stanRAB the test of time for me. The Elric brothers are great leaRAB, and the relationship between them is wonderful as they search for a cure to their problems, finding only more problems along the way. I cried several times over the course of the series, and I found myself quite attached to the cast.
10. ZoiRAB: Chaotic Century - It's a great series that doesn't get nearly enough love. Van is a great lead, the entire cast is great, and the storyline is just a joy to follow. I love the various incarnations of the Liger and Zeke is awesome. And Raven