To the Community:
I have some fail builds... This is the first build that I am truly going to work on.
Singed is one of my favorite champions. Not that he's overpowered like unnerfed Twitch (yes, I know, wards/oracle, stun, dps, dead), but that he's extremely fun to play.

Help me improve this build.

What does Singed need?
Well, he needs movement speed to catch up to enemies so he can fart in there face.
I guess mana would work, because it synergizes with his passive: Empowered Bulwark which increases his HP by 1 for every 4 mana.
Also, if you want to hit for more, Ap would work well too.
Personally, I think singed is an offtank that is mostly utility (unless farmed, then he's really scary), so Tanky items would suit him well.
So what we need is:
Movement Speed
Mana
Tanky items that fall under the two-categories.

So the runes I would choose are:
Spell penetration marks, because singed spells don't do much damage unless built as a caster, at which point his spells do ****loads of damage. I might as well get as much dmg as I can out of poison trail

Mana Glyphs per level, because throughout the game, it will give small bonuses to health and mana... It works well with the innate.

Health Seals, because it works well with when you charge up to people to fling and helps my poor early gaming... Feel free to change the seal to armor and health regen, it's just my style to get flat health.

For quintessences I get movement speed for an interesting amount of burst speed starting the game without boots and having 334 ms is fun...

In the masteries, I decided to get anything that improved movement speed and the summoner spells that I've chosen in this case exhaust and ghost... I gave 9/7/14 masteries, because I really want that spell penetration, it makes it so that despite me not being a full caster, my spells do some real damage... I get the strength of spirit, because you WILL have an immense mana pool by the end of the game, this gives you a nice hp regen. With 14 in utility you might think... Wait, I thought we wanted movement speed! Well movement speed is good with singed, but speed doesn't kill, whereas the point will be used in strength of spirit utilizing the fact it will help your survivability. Resistance is taken instead of the armor for two reasons:
1. It builds into strength of spirit
2. Physical Carries people can't catch you*

*usually DAMN YOU TO HELL ASHE

Movement Speed
Mana
Tanky items that compliment the above. That is what we need
Ap would work too...

Items that compliment

Fling is taken at level 1, because it increases your chance of first blood by that much.
Then max poison gas asap, because it is your main farming and harassment skill. Take Adhesive when possible so that it slows more. Fling is maxed last, because the range it is thrown does not scale.

Summoner spells have to work well with singed.'
Ghost makes you move at hilarious speeds, perfect for chasing and escaping.
Cleanse will remove those slows and stuns, also great for chasing and escaping.

These could work...
Flash :can be used for flash flings. Trust me its hilarious. What happens is that you are in a bush and you suddenly flash out and fling them toward your awaiting teammate(s). Also, used for chasing and escaping. I personally find it rather good, but not as good as ghost. It's an all character skill. Take it if you want.
Exhaust :used mainly for the slow. Now that they removed the blind, it makes it less viable in my mind.

On the fringe: (unless you're real good with them)
Clairvoyance: Take a peek and fling outa that bush
Ignite: If you really want a first blood, but not that necessary
Fortify: If the jungler seems a bit new... Choose this
Rally: Herp seen it work before

Why?
Smite: Really?
Revive: You could use the movement speed. But being so tanky, you wont die.
Heal: Slows down your healing afterwards (desynchronization with insanity potion)
Clarity: You got enough mana.
Teleport: You move fast enough.

I usually start out with a regrowth pendant and a mana potion.
Upgrade it to philosopher's stone asap: The mana regen and hp regen is great plus the extra gold is a nice touch. Rush your heart of gold. Then get boots of swiftness.

During this early game period, try to last hit minions (like every other character), and if you see an oppurtunity, fling them into your ally. I usually lane, singed might be able to solo mid, but it would be pretty hard... The enemy carry is usually in mid, so they would get a lot of lasthits, due to your rather shortrange harassments.
Simply Put... FARM FARM FARM

Good allies to lane with are:
Sion. Oh god. A two-second stun for you to run up and fling them. I've died so many times to this combo. It's just frightening.
Disablers in general: Stuns, snares, super slows (im looking at you nunu), knockups, frost, anything to let you run up and fling them. Fling is your main skill. Poison gas is farming and damage, but a proper fling makes or breaks a singed. Learn to use it, because if you fling in the wrong direction, it just wont work.
Carries: If you can lane with someone like Xin or Ashe, because they can disable, deal a ton of dmg and if you help them get some kills, they become unstoppable killing machines.

Please comment. First... useful build that I've made...
Damn, I thought a build would be easy to make, but actually it takes a helluva lot a time.
O.O
I encourage people to make builds, I like people looking at other people's ideas, it helps people improve and specialize at certain things.