For Sword Art Online you should really just read the light novels (the anime, as said before, is a solid 7/10 when taken from the whole -- which includes future episodes). It flows better and makes a lot more sense. And don't skip the side stories; some of them have extremely important plot points.
Accel World (complete as of now, at least for this season) is pretty damn good. 8/10 at least, sometimes crossing into 9/10 territory. The protagonist is also a hell of an anti-Sue, which is always nice. I still don't know why Accel World is better than SAO, considering they're both anime adaptations of light novels written by the same person, but whatever.
Continuing the light novel trend, Fate/Zero (100% complete now) was pretty good as well. A solid 8/10, though a few moments are just 10/10 spectacular. Just don't try watching it if you've never seen and/or played Fate/Stay Night, since a lot of stuff won't make any sense. After all, the light novel was written as a Forgone Conclusion type of story, seeing as it's a prequel to the Fate/Stay Night visual novel. Edit: Watch the blu-ray version! It includes a lot of cut and censored content and runs something like two hours longer than the TV version.