Fate/Stay Night
Shingetsutan Tsukihime
Shakugan no Shana
Mahou sensei Negima!
Ookami to Koushinryou
Chrno Crusade
World Embryo
I really like a lot of manga, and I had to choose between my top 50. But, I think this is my top 7. These aren't really in any order (I might change em up).

Being alone is only lonely if you want it to be.
Staying in lucid delusion for an eternity.

akuma na eros

perfect girl evolution also known as the wallflower.

skip beat

Bishounen no Oheya

Osaerarenai!

best ever 2 of them are also animes the others not so much but yeah, im absolutely in love with every one of these mangas so much that ive read them over again (except for the anime one cuz there like 208 chapters i just watch the anime over again) and i almost NEVER read a book or manga more than once. it drives me insane to read something twice becuz after i read something once i remember pretty much all of it. so these are REALLY good for me to be able to stand reading them over again 😀

If I really have to choose...
Elfen Lied

Other memorable ones are:
Our Dear Tamura-kun
Girlfriends

Complete-
tsubasa reservoir chronicles
black cat
fma
xxxholic
love monsters
and oddly enough pretear

Ongoing-
black bird
bleach
kuroshitsuji
and so far mitsuiro devil looks good but we will see

trc & holic are masterpieces, gotta read em both, but to get the best out of it either read em together or read trc 1st, I think.
I would do horrible, terrible, rotten, & despicable things to read more black bird. Seriously, I would sell my soul & everything else I own (except my anime collection, thats my pride) for it.

1.- Nodame Cantabile
2.- Nana
3.- Midnight secretary
4.- The One
5.- Skip Beat
6.- perfect girl evolution
7.- Koukou Debut

top five off the top of my head

Emma
Love Hina
Arigatou
One Piece
Rave Master

Sarcasm just doesn't work over the internet.

Dengeki Daisy
One Piece
Kanata Kara
Beauty Pop
Death Note

1. Monster & Shiki tie for first.
2. Vagabond
3. Historie
4. Cesare
5. Vinland Saga

"Alone, I send out signals...to the mermaid that will never show up."

Natsume Yuujinchou
Dokuhime
Full Metal Alchemist
Card Captors Sakura
Heroine Shikkaku
Liar Game
Oresama Teacher

GAHH, I couldn't limit it down to 5, nor can I place them in order.

1. Kaikan Phrase
2. Haou Airen
3. Black Butler
4. Darker Than Black
5. Skip beat
   So hard to limit it to 5 :'D

Naruto
Bleach
The World God Only Knows
History's Strongest Disciple Kenichi
Yureka
Nononono

            lol my top 6  screw 5                                  😎 

Chidori
[img]http://fc05.deviantart.net/fs70/f/2013/265/0/6/sasuke_chidori_3_by_bobelite12-d6nhbfq.gif[/img]

Not in order of favoritism 😉 But these are the 10 most memorable ones.
Deep Love (all of 'em, especially Ayu's) 😁 -it was one hell of a series.
Princess-I'll never get tired of this 😀
Black Butler-Only shonen manga that I'm still reading. 😃
Versailles no Bara -Oscar is the most decent shojo heroine EVER. 😎
Hoshi no Koe-The only mecha anime-manga I've managed to cry on. 😢
Hana to Akuma-I followed it's releases for 2 goddamn years. 😳
Hana Yori Dango-It's probably one of every girl's favorite 🤢
Kiniro no Corda-the only anime-manga that got my mom hooked. srsly.
Bleach-the one that started it all for me 🙂
Tsuki no Shippo-got rid of my hatred for ninjas :* 🙂

Though I have no favorites and I forgot the ones I really liked 🙁 , I rarely see a manga which can influence me. 😁

Every minute you're sad, you lose 60 seconds of happiness.

Bakuman
The World God Only Knows
Hayate no Gotoku
Detective Conan
Iris Zero

and Liar Game, though it's currently on hiatus 😢

Dengeki Daisy
Skip Beat
Basara
Mars
The Breaker

Hmm and although its not manga but a web-comic .. Noblesse is just ahmazing!

Update~

One Piece Has forever been, and forever will be my number 1
Berserk Epic
Noblesse Not technically manga, but awesome nonetheless
Toriko So much fun!
Gintama Still hilarious (though apparently nobody else is interested in the manga [in the US])

[img]http://www.nodiatis.com/pub/21.jpg[/img]