My favorite manga is currently ARIA (and its prequel, Aqua, but they’re pretty much just the same series with the first two volumes published under the name “Aqua” and the other twelve under the name “Aria”). It was the very first manga that I ever read. My sister left her manga collection behind when she moved out when I was 11, so I invaded her room and the first one I picked up was Aria. She had the first two volumes, and I fell in love with the simplicity of the whole thing, the cleanliness of it. The covers are gorgeous, colorful, landscape style works of art, and are, in my opinion, the prettiest manga covers I’ve seen to date. Sadly, it has never been fully published in English, although you can find it translated online.
Since I don’t believe many people know of Aqua and Aria, I’ll give you a brief idea behind the series. In the words of the first book, “…terraforming on Mars has caused the polar ice caps to melt, covering 90 percent of the planet’s surface with water and making it habitable for humans. Mars is now referred to as Aqua, the water planet, while Earth has become known as Manhome. On Aqua lies the port town of Neo-Venezia, which is modeled after the Italian city of Venice.” The premise is that in the year 2301, the main character, Akari, comes to Aqua to train at Aria Company as a gondolier, known on Aqua as an Undine. It’s a slice of life story that moves at a pretty leisurely pace, so impatient people may have a harder time getting into it, as there isn’t much plot besides the day to day life of Akari and her friends as they work towards becoming full-fledged Undines in Neo-Venezia. The art is good, the story sweet, and I enjoyed getting a good bit of interesting Venetian history while reading it. Another reason I enjoy it is that each book takes place in another season, and I really LOVE watching and experiencing the changing seasons in real life, of course, so I adored getting to look forward to the books taking place in each season, and especially autumn, as it's my favorite. But the bigger reason behind my loving the series is the fact that it helped to change my outlook on a lot of things. To be brief about it as I’ve already written too much, it helped me to get rid of my rather gloomy outlook on things, and taught me that even the smallest of things in life can bring delight, which is something that I now live by every day. ♥
I have yet to watch the Aria anime, so I don’t know if it is as good as the manga. Others I’ve enjoyed throughout the years have been Pita-ten (both the manga and the anime), which is another one that I got into from a young age, Black Butler (just the manga), Death Note, Haibane Renmei (which is gorgeous), Le Portrait de Petite Cossette (anime is better than the manga), ShutterBox, and all of Miyazaki’s works, as he’s incredible. Also, although I didn’t finish these, I really liked what I did read of Kaori Yuki’s Angel Sanctuary, Godchild, and Grand Guignol Orchestra - although that may just be because I love Kaori Yuki's artwork. That’s certainly not the extent of all I’ve seen or read, but those are what I can think of right now that stick out in my head as memorable, good ones that I really enjoyed or that made an impression on me in some way, I guess.
I suppose my measurement of “favorite” has ended up being “how much I’ve changed from reading/watching this”, which is why Aria gets the top spot for me - not that I find it better than others, but that I identify with it and it changed me. :> ♥
Fairy Tail, Code Geass, Tsubasa Reservoir Chronicles, Tales of the Abyss, DNAngel, Naruto(Manga Only), Bleach(Manga Only), Infinite Stratos, Black Cat, Card Captor Sakura, Angelic Layer, Angel Beats!, Rosario and Vampire, Familiar of Zero, Full Metal Panic!, Full Metal Alchemist, Gurren Lagann(FTW!), H.O.T.D(Don't ask!), Hetalia, Inuyasha, K-on!, Ryuusei no Rockman(Megaman Starforce), RomeoXJuliet, XXXHolic, Yu-gi-Oh, Pokemon, Kaichou wa Maid-sama!, Van Hellsing(And Van Hellsing Ultimate), Death Note(Manga Only), Vampire Knight, One Piece, Foolie Coolie(Or whatever it's called...), The Melancholy of Haruhi Suzumiya, and Lucky Star.
Phew! That was one long list... XD
My faves are Fairy Tail, Naruto, Bleach, Code Geass, Tsubasa Reservoir Chronicles, Gurren Lagann, FMA, and Card Captor Sakura.