I really enjoyd Blood+, actually. It just fell apart in its final quarter.
Anyway, some really bad anime that I managed to finish somehow (I'm stil not sure why) and that haven't been mentioned:
- Shining Tears X Wind. Honestly, you can't get any cheesier than this one. Episode 12 has got to be the most painful anime-episode I've ever seen.
- Afro Samurai. Gonzo seemed to believe that Samuel L Jackson and action were a guaranteed success for this movie, but it turned into a horribly predictable action-flick.
- Giniro no Kami no Agito. Again by Gonzo, and yet aagain it likes to include useless action and a Mary Sue main character.
- Girls Bravo. This one's basically the biggest reason why I dismiss most fanservice-anime (see TCoFA's comment). The entire plot is basically one huge excuse for fanservice, and it contains more clich?s than you can imagine.
Though with the worst ones I never even went beyond the first episode. Here are some of the more notable ones:
- Zaizen Jotaro. This is probably the anime with the longest title ever, though I abbreviated it here because I can't remember. It features one infamously bad scene, in which our main character makes his entrance, piloting a hypermodern private jet, and ejecting to his place of destination. What happened to the jet, we'll never know. It's basically about a guy who spends way too much money, tracking down government officials who spend way too much money. The irony.
- Saint Beast is a good contender for the award for most boring anime ever. It only took one episode to put me half to sleep, imagine what 12 episodes could do.
- Yoake Mae Yori Ruri-iro na ~ Crescent Love. I've seen a LOT of bad harems up till now, but this one is exceptionally bad. It features the premise of a princess from the moon who comes to live with the protagonist in order to get used to earth's customs. Why? Because he helped her once when they were young.