*cracks knuckles* Oh there's a lot...
In the action/Shounen stuff, Mahou Sensei Negima (and its successor, UQ Holder) is king. Followed by World's Greatest Disciple Kenichi. Flame of Recca holds a special place in my heart as one of my earliest manga series. Meanwhile, for more recent stuff, My Hero Academy has been doing far better than I expected. Special mentions go to World Embryo and Psyren, for interesting supernatural stuff.
For comedy, The World God Only Knows is awesome. So is Yotsubato&! (and totally adorable and I hope to chaos that when I have a kid, they will be just as adorable).
I'll add more, maybe, when I think of it.