I was going to ask what people were recommending nowadays. So, if people have other suggestions, especially if they are available on Netflix or Hulu, that'd be great. Edit: I'm an anime but not a manga fan.
Personally, I echo other people's suggestions. Code Geass, Cowboy Bebop, and Bleach (though it has begun to drag lately ...) are all great. My feelings on Hellsing are mixed ... it's mostly just a mayhem fest. Which is enjoyable, but I hesitate to call it really "good." Oh, and I like FLCL, but it's kind of (well, a lot) meta.
And, Naruto. SorO is totally right about it. I mostly despised it when I first watched it. It was occasionally watchable, if only for glimpses of cool interesting powers and the fact that I liked about 4 out of a cast of thousands. But, I just made it almost through the Pain arc in Shippuden and ... wow. I was literally shocked at how good it was. I'd almost just suggest starting towards the end of the normal show, right around when Jiraiya shows up maybe?, and then going into Naruto Shippuden. It won't be too hard to follow what's going on: the show explains things a lot (and I assume the manga does, too) since it's pitched at a younger audience.
P.S.: pardon the ignorance, but what's T4?
I personally loathe Naruto and its fanboys (not that I'm implying you or anyone here is a Naruto fanboy, for the record) for myriad reasons, but I know opinion is not the same as statement of quality. Lots of people like it, and I suppose if there wasn't SOME good to it, it wouldn't have survived this long as a series. Personally, I'd add One Piece to the list - it's weird as all hell, but the entertainment factor is undeniable for fans of shonen and comedy. Oda managed to do something that I'd only seen Masami Kurumada pull off before: create a hit series with a drawing style that does not cater to any illusions of stylistic beauty. Unlike Kurumada however, he hasn't gone off the deep end of madness with success and greed.
I like Hellsing, particularly Ultimate, for two reasons: Rule of Cool is stressed above everything else (it's the whole point of the freaking series), and VAMPIRES ARE MONSTERS (this is stressed so many times that "I/we am/are monsters" is a quote only second in coolness in that series to "The Bird of Hermes is my name, Eating My Wings To Make Me Tame").
I STRONGLY second Cowboy Bebop. Manga followed the anime, but both are very enjoyable in their own right. The manga doesn't have a soundtrack, which is the series' highest point along with the colorful characters, the awesome plot of each episode (unlike most series, there are no arcs with definite plots; only two or three-part episodes), and the comedic moments.
Haven't watched Code Geass, though the manga was quite enjoyable. Less mecha action than the anime, which may or may not be a good thing depending on what you find yourself enjoying.
Speaking of Mecha, I'm surprised no one mentioned Gundam yet. There's a lot of different Gundam series and each has a flavor for a different audience. The first few series all occur in the same universe over a given span of time, so there is a chronological order to them, but the rest is pretty much independent.