Here is my response to The Mask's post on the Watercooler, asking people to name their Top 10 anime of the decade. My choices in no real order are...
1) RahXephon - Sometimes decried as an Evangelion clone, this series is so much more than that. Sure they share some mecha anime cliches: young pilot(s), a mysterious organization charged with defending the world, a constant stream of giant aliens/monsters to fight. But beyond all that RahXephon plays with the concepts of time and music in very original ways. I also think it has a level of maturity in it that Evangelion lacks, and while the ending is also a tad confusing, it's far more satisfying. This series more than deserves to stand on it's own as a defining piece of art.
2) Black Lagoon (incl. Second Barrage) - If Quintine Tarantino were going to make an anime, it would most like resemble Black Lagoon. Everything about this series as watched it pushed my boundaries: the setting, the characters, the language, the operatic levels of violence. There's a raw power to this show I found very appealing. Probably the best of everything out that that's dark and drenched in blood.
3) Fullmetal Alchemist - Besides just being a brilliant show with a great setting, story and cast, FMA was also the series that proved FUNImation could do incredible things. From here on they just got better until now they're the king of what remains of the hill after the collapse of Geneon and ADV, and it all started with FMA.
4) Haibane Renmei - The anime that affected me the most at the time I first watched it. It starts off as this rather light fantasy/slice-of-life show, but as it progresses the emotional floodgates are open and you find yourself pulled in ever more by the emotions of the characters. The first anime that made me cry, it will always remain one of my favorites and just a beautiful series, both visually and emotionally.
5) Mobile Suit Gundam 00 (Seasons 1 & 2) - For a long time, I had lost interest and faith in the Gundam franchise: Wing was just painful and laughable to watch after all these years and SEED was a travesty. I didn't pay much attention when I heard about another new Gundam series coming out, but when (then) SciFi aired Season 1 of 00 and I watched it, it revived my fading hope that the franchise would ever produce anything truly worthy of praise. This to me is the definitive Gundam series: the politics are not sloppy like Wing, the characters are more interesting and so are the Gundams themselves. And being the first Gundam to be set in the real-world timeline, 300 years or so from our own time, and reflecting our current concerns of energy supplies, this series feels like it could potentially happen. And while Season 1 was good, Season 2 blew it away. If I were ever to recommend a Gundam series to someone who hasn't seen anything in the franchise, it would be this.
6) Honey & Clover (Seasons 1 & 2) - Like Shin said in his list, this is the comedy/drama/romance that transcends the cliched high school genre. The comedy is right on point, the characters are genuine, the drama and romance aspects are well handled... This is 'grown up' in a way a lot of shows of this kind aren't.
7) Maria-sama ga Miteru (all 4 seasons) - A series about the friendships/relationships between a group of girls in a Catholic school. Not something everyone is going to enjoy, and when I started this I wasn't too sure about it either. But as I watched more and got to know the characters, I just couldn't help but fall in love with it. Although classified as 'yuri', it's more on a classic level of what was once called 'romantic friendship', where two people (no matter what their gender) have very intimate ties to each other, but are expressed in a more idealized way rather than physical romance. Having seen other yuri series since, I also enjoy how Marimite is still more down to earth than most, dealing with emotions and misunderstandings that genuinely happen when you're a teenager, whereas other shows go too far down the soap opera path.
8) Full Metal Panic! (incl. Fumoffu & Second Raid) - Mecha, high school, wacky hijinx... One might not think these elements can go together successfully, but FMP! proves that it can. It manages to balance mecha action with drama and comedy in just the right ways and proportions. And you have your pick: first season balances it all just right, second is all comedy, and third is much darker and slanted more heavily to the drama side. This is definitely my second-favorite mecha series after RahXephon.
9) ToraDora! - Until this year, I hadn't really watched any comedy/drama/romance shows. I didn't really think I'd enjoy them... but then ToraDora! proved me wrong. This is simply a great show from beginning to end, and one of if not the best among the high school series.
10) Clannad & Clannad ~After Story~ - Can't really separate these two. Clannad was the next one to really hit the heartstrings and make me cry. Not really a harem series, although the focus is on one main guy and the scores of girls around him. And how many shows go from high school to the rest of the character's lives? Not any that I know of. Just achingly funny, beautiful, and heart-breaking in equal measures.
Honorable Mentions, or Ones That I Wanted to Include but Ran Out of Room:
Nodame Cantabile, Noir, Chrono Crusade, Romeo x Juliet
