Hmm, that's kind of a hard question, lol. Umm, probably the first thing that strikes me as having really a memorable ending, specifically, is Code Geass. But, I mean, there's a lot of series that I still remember the ending of, lol
I was very interested in the Nisekoi anime, I haven't read the manga in quite some time but hoped to get motivation again with the anime. Shaft now working on it with Shinbo at the helm. Oh my goodness I am ready for this.
It was alright. To be honest, I wasn't a huge fan of the last arc. The whole bit about the little girl assassin (who I found, frankly, a pretty boring character) and Iwai being connected was just pointless, and the whole idea of the Order Made Authors doesn't feel like it has any purpose other than to give the mandatory evil organization something to do. The whole thing with Kiri and Grayland was pretty good, though. And I still like Kiri and Iwai as characters.
Thing is though, it ended I expected. By that, I mean it didn't end. The series just stopped, building to another season that will almost definitely never happen (a trend that I absolutely hate, by the way).
Well, I don't really abide by the three episode rule, but as far as shows I'm still watching this season:
Red Data Girl
Aku no Hana
Devil Survivor 2
Shingeki no Kyojin
Valvrave (but only because i can't resist sunrise's shiny mechs)
That I am. However, I live in Australia where it will likely come later, and I don't have a DS anymore. Etrian Odyssey was a quirky bit of fun while I had the various games on my flashcart, to be sure.