Here is a list of Manga that I have completed or am currently reading. I am fishing for recomendations as well, so if you have a favorite, lay it on me!
Basilisk - enjoyed the anime as well.
Bitter Virgin - This is the first manga I read. Wow...blew me away. Gave me a tast of seinen manga. Very, very sad story line. Very beautiful artwork. Much like Blood+ anime for me; without Bitter Virgin, I would not likely have picked-up a second series. (please note the shameless reference to Blood+)
Claymore - Manga was way, way better than the anime. Haven't completed it all the way.
Elfen Lied - Holy crap...best manga ever. The one thing more brutile and violent than the Elfen Lied anime is the Elfen Lied manga. Loved it so much, I got the last four volumes in Japanese just so I can look at the artwork.
Fruits Basket - Loved the anime; manga was so bad I have stopped for a few months. Some tv.com friends have strongly recomended giving it a second chance.
Futari Ecchi - Hypersexualized. A suprisingly insightful and touching story about a young, inexperienced couple learning to love each other. Classified as ecchi, but is really a touch farther.
Gantz - Manga was as bad as the anime...got about equally as far in each before giving it a rest.
Girls Saurus/Girls Saurus DX - From the author Bitter Virgin. Comedy about a young man who is terrified by women. Some rather strange reflexivity; instead of the hot girl being hounded by guys, it's the hot guy who is hounded by girls and can't seem to get away from them.
Hatsukio Limited - Not much has been translated into English. More school life genre. Fair manga. Read it mostly because I liked the author/artist's other work.
High School Girls - Strangely entertaining. Not overly comedic. Touching story of friendship and coming of age from a feminist perspective. Wish I could have read this about 25 years ago; may have gained some insight from it. But then again, I was a complete idiot back then.
Inuyasha - Not very far into this very extensive manga. Manga is much better than the anime...and I liked that anime.
Kanokon - Started off strong...then what the hell happened? Not much has been translated into English.
Lilim Kiss - Liked this one very much. Sort of a love story...but the subtext is about boundaries and self-identity.
Love College - Didn't get very far. A comedy about male compartimentalization of women's bodies. Not very insightful. Anybody ever hear of a teen age boy who didn't like boobs? Yeah, no suprises here.
Love Hina - Manga was much, much better than the anime. A story about how love endures and aobut how different people understand their own hearts in different ways. This story is simultaneously touching and frustrating. But the subtext is poignant: the bonds we share with the people we love can be very strong, very real.
Moon Phase - Manga was better than the anime. Fairly entertaining. Often a comedy, often a drama.