What is your favourite anime ?

Wow, Shiki! Good choice.
Mine currently is Yu Yu Hakushi.

Cowboy Bebop and Ghost in the Shell, with some others up there. I don't have one "favorite" of all time, but those two are pretty solid. I prefer the GitS first movie (and maybe the second) but the rest of the stuff is good except for Arise. I'm on the fence about Arise.

Neon Genesis Evangelion, Cowboy Bebop, FLCL, Lucky Star, So Ra No Woto (Sound of the Sky), Death Note, The melancholy of Haruhi Suzumiya.

magical lyrical nanoha,magical madoka,stein gate...

grappler baki story isn't anything special but tonnes of fighting in it some brutal parts

one punch man + naruto

Weiss Kreuz, Get Backers, Paranoia Agent, Hunter x Hunter and Hellsing+Ultimate.

Princess Tutu. Seriously.

Saint Seiya and Dragon Ball

I don't really like anime. But for favorites. Full Metal Alchemist. I also like Blue Exorcist and Mushi-shi.

To Love-Ru, SAO, Steins;Gate, No Game No Life

Ghost in the shell, it touches in a lot of interesting subjects.

Fullmetal alchemist Brotherhood liked it a lot.

Steins Gate was very enjoyable.

Jinrui wa Suitai Shimashita (Humanity has declined) was something weird and enjoyable.

For me i have quite a few....
Hataraku Maou Sama
Hyouka
Hikaru no Go
Log Horizon
Oregariu
One Punch Man

I am not super big on anime but this is what I liked besides obvious ones like Trigun, FullMetal and Naruto:

School Rumble
Generator Gawl
Gundam Wing
Outlaw Star
Seven Deadly Sins (loved more than I thought I would)
(and DBZ because duh)

Teen Titans count?

Katekyo Hitman Reborn!
Hunter X Hunter
Kill La Kill
Tokyo Ghoul
Ao No Exorcist
Seven Deadly SIns

(Havn't watched much, most of which are long running anime which is slowing me down, but these are the ones that kept me the most entertained and that I enjoyed.)