I was thinking i'd make a champion counter list! But i'd love your help! Post counters for junglers, solo and duo lanes! And i'll put characters that simply doesn't counter and doesn't need to be countered on the Useless character list! (all up-voted (+2 votes) comments come on the lists!)

Solo lane:
Akali: Skillshots, Sustain, Long range. For example Swain, Gragas and Kennen. (and Lee Sin, general counter for stealth) High health counters Akali very well also.
Alistar: Amazing Sustain, Alistar will get oom. For example Warwick, Nidalee and Nocturne.
Anivia:
Annie:
Cassiopeia:
Cho'Gath: High sustained dmg that doesn't rely on spells. For example Gangplank and Nocturne.
Galio:
Gangplank: Higher burst, Dorians shield. For example Rumble, Vladmir and Teemo.
Garen:
Gragas:
Heimerdinger:
Irelia:
Jax:
Karthus:
Kassadin:
Katarina:
Kayle:
Kennen:
LeBlanc:
Lux:
Malzahar:
Mordekaiser:
Morgana:
Nidalee:
Nocturne:
Orianna:
Renekton:
Rumble:
Tryndamere:
Udyr:
Veigar: Long range
Vlad:
Warwick:
Yorick:
Zilean:

Junglers:
Amumu: Gank before he gets blue and he's gonna jungle very slowly.
Fiddlesticks: Gank before he gets blue and he's gonna jungle very slowly.
Gangplank
Irelia
Nasus
Nocturne
Rammus
Shaco
Trundle
Tryndamere
Udyr
Warwick
Xin Zhao

Ad Carries
Ashe
Caitlyn
Corki
Ezreal
Miss Fortune
Sivir
Teemo
Tristana
Twitch
Urgot
Vayne: Lee Sin, General counter for stealth

Supports
Alistar
Janna
Karma
Kayle
Sona
Soraka
Taric
Zilean


Useless characters:

Nunu is a good jungler and counterjungler himself. Nomnom those wraiths.

Not really, he becomes a decent ganker at lvl 9 and then its too late. hes basically useless end game so...

You misspelled "Jungler".For Veigar- counter is long ranged champions that dont use ap.Caitlyn, Kogmaw even ryze can counter him if he builds right.Banshee's Veil also ownes him.

lee sin is a counter for akali,because his skills will reveal akali.
and you forgot lee sin from junglers

Akali is countered by Lee sin and other tanky champions.
Anivia= Brand and Orianna
Annie= Swain, Kennen


Nah i dont bother :>

Both amumu and fiddlesticks rely on bluebuff to keep themself sustained in the jungle, gank them at blue buff and they are gonna get behind.

Tryndamere: Hard cc and ignite 2-3 seconds into his ult

Lee sin is stealth counter. Akali and vayne can't hide themselves for even a split second once he's revealed them.

annie can be counter by long range champions,like kog'maw or lux.