Well, depends what you want to say with the word "favourite". Favourite like "I could watch this everyday of my life?". Than nothing because after the first watching you already know the plot. It´s not the shocking like at the first time :D If favourite means for you something which really impressed you, than I would say to animes:
a lot (Ghost in the Shell 1 + 2, Elfendlied, Death Note, in this moment Code Geass, in generally every well drawn anime with a good story)
sorry, I don´t read mangas.