What anime should I watch next?

If you're looking for an amazing anime with brilliant storyline and are fine with little to no fanservice, i recommend wholeheartedly Fullmetal Alchemist: Brotherhood. and if you are fine with reading the manga i'd say read that too! It's definetly the best anime/manga out there!(BTW you can watch this on youtube in glorious 720p with different language subtitles in select countries, i'm fairly sure it's blocked in GB and most likely in the USA, but elsewhere is anybodys guess)
Also if you are in search of some classics here are a couple:
Lupin III (about a very famous thief, orchestrating and executing the most preposterous of heists. it's a series, fairly old, around the 90s-00s)
Cowboy Bebop (about a bounty hunter in the year 2071, various adventures and shenanigans, fantastic art and a brilliant soundtrack worth watching for)
Ranma 1/2 (a typical shonen anime/manga about a boy that becomes a woman when doused with hot water and reverts to a boy whit cold water, panty shots aplenty and shenanigans galore)
GTO (very interesting story following a young "ex"-delinquent teaching a class of rowdy pupils, filled with many interesting developments)
will add more when i recall other ones i'd recommend

Don't forget to watch Code Geass, I can also recommend Soul Eater. Don't watch Guilty Crown (really don't).
You can start some long series like Bleach, Naruto, One Piece etc.
After seeing lots of animes and getting into anime culture, you should watch Gintama :)

Steins; Gate.

I make some anime list which I wached and I liked,some of them comedis,some detektives, hopes you like them ( Kuroko no Basuke,Gin no Saji,Hajime no Ippo,Yakitate!! Japan, Blood Lad,Kami-sama no Inai Nichiyoubi,Amnesia ,Aoki Hagane no Arpeggio,Unbreakable Machine Doll,Hagure Yuusha no Estetica,Gekijouban Hana-Saku Iroha,Shingeki no Kyojin, UN-GO, Hakkenden,Rozen Maiden,OreGairu,Genshiken Nidaime,Mushibugyou,Fairy Tail,Ao no Exorcist,Darker than black).

Dragon Ball and Dragon Ball Z maybe
(plus it has more than 15 movies)

Kuroko No Basket is like one of the best anime I've ever watched :D

Try Devil May Cry , Blue Gender and Yu Yu Hakusho, you`ll be surprised by this too ( I wont say Dragon Ball since was already mentioned, but ye DB series is a must watch too :P)

Dead Man Wonderland

Another

Miraii Nikki

Darker Than Black

Fullmetal Alchemist and Fullmetal Alchemist: Brotherhood.

Devil May Cry

http://myanimelist.net/animelist/RonDBlade (no idea how to make a clicky)would recommend most of list,but you should really watch mirai nikki,code geass and naruto

Code Geass

Campione!

Mirai Nikki

Seitokai no Ichizon

Accel World

If you'd like something more serious and philosophical, I'd suggest Ghost in the Shell. Best anime I've ever watched.

Nichijou. I don't know why but you should watch it.

Angel Beats

Attack on Titan.

Mirai Nikki (The Best), Accel World (Nice One), Steins Gate (As good as MN), C (LOL, Crazy but F*cking awesome)

Fairy tail is great. FMA brotherhood is a classic and I still find that as the best anime ever. Unbreakable Machine Doll is really good, but be warned it is ecchi so there are girl butts and barely covers breasts along with sexual jokes all over the place BUT it's still really funny, has great characters and the plot is pretty good. If you haven't watched it yet then you're living in a cave. Attack on Titan is pretty much the most hyped up anime right now. Idk a single anime viewer who hasn't seen it yet. Now to me (along with many other people) after around episode 20 it gets really stupid. The plot just takes the biggest nose dive and the manga isn't really any better after that point. D-frag is super funny and really new. New episodes come out on mondays also Witchcraft works is pretty cool too. Same thing like D-frag it's new (came out the same time I think) and new episodes on mondays. I can't think up of anything else right now so check these out. They're all pretty short except for Fairy Tail. It's at 175 episodes right now and next anime season a new season is going to start so you're going to have a lot of catch up to do. Other than that D-frag and Witchcraft works are both at 10 episodes, Attack on Titan at 25 episodes, FMA brotherhood at around 60-70 episodes and Unbreakable Machine Doll at 12 episodes along with a little prologue special that's about 5 minutes long. Just adds in a couple extra minutes before the first episode and throws in some more sexual jokes. It seems childish, but trust me it's a really good show.

My top 5 recommendations:

1. Angel Beats! (Very well-made, and very good characters. Sometimes funny, sometimes sad.)
2. Elfen Lied (Gory, but epic story/characters.)
3. Helsing (Good Action/Cool characters.)
4. Corpse Princess (Same, good action, good storyline.)
5. Kore wa Zombie Desu Ka? (Great action, great humor.)
   Extra recommendations: Cowboy Bebop, Ghost in the Shell, Mirai Nikki, Code Geass, Clannad, Another, Kaze no Stigma, and Darker than Black. These aren't worse than the others, they're just ones that I haven't finished, or don't like as much, or weren't as "special" as the others, but they're still awesome, lol!

Photon.

My top 5 anime list that you should give a try:

1 - Full Metal Alchemist: Brotherhood.

2 - Cowboy Bepop.

3 - Evangellion (The original + The End Of Evangellion movie, not the shitty remake)

4 - Wolf Rain

5 - Mushishi (Sorry for putting it in this position, but i really have a special place in my hearth in animes above this one, not that this doesn't have one too you know XD).

Angel Beats, Attack on Titan

Some of my favorites are: Neon Genesis Evangelion (best one in my opinion), Cowboy Bebop, Tengen Toppa Gurren Lagann, G Gundam, Madoka Magica, and some movies like Redline, Akira, and Ghost in the Shell.
Also, Really enjoying Space Dandy on Adult Swim. Also, avoid shonens like the plague they are, and remember the teachings of Tyrone and Rog. ALSO NOTE THAT THE EVANGELION REBUILDS ARE NOT A REPLACEMENT FOR NGE, WATCH THEM AFTERWARDS IF AT ALL.

Fairy Tail is my all time favorite, can't wait for next season, followed by Attack on Titan and Space Dandy, SD is pretty funny to watch

One Piece