High King Thorgrim...
Pretty cool model, evan better story.. thats one angry dwarf and as far as game play goes.. he is one hard bloke!
Gotrek is also VERY cool, I cant get enough of his books and the fluff you see in spots and he was also a force to be reckoned with back in 4th ed, I wish they put him in 7th ed.
I like the model where he is carrying the trolls head!
Anareion, the first and greatest Phoenix King. (Yes I play High Elves too) :p
Possibly Nagash. So... much... power! Although I like Egrimm Van Horstmann too... Not sure I have ONE favourite to be honest...
AHHHH I forgot about NAGASH! How awesome is he!! I should be whipped for forgetting about him, Such a powerful chacter on the board and in the stories... now there is some fluff that you just cant get enough of.
I wish they wrote books about him!
Also reminds me I must get my Nagash painted up... seen any good paint jobs done on him?
Tzar Boris. Greatest mini ever.
Astragoth !!!!!!!
*whips Deebo* Join the Dark side, I cannot. Pervailer of the Light, I am.
Feck it, Evil FTW!
Hmm, now you mention him, Nagash is pretty cool as well, but I've got to go for Bugman. Come on, a Dwarf Masterbrewer. Nothing can beat that, he even has his own real-life pub, figures, etc.!
Thorgrim's ok, and so is Gotrek. Pretty nice/good fluff & models (one's fluff is better, one's model, obviously which one), but both not coming close to Bugman and his .. one, two, three, four, five versions.
I wish they wrote books about him!
well they are look for your self just click comeing soon in the top left corner
Godbob, you are a bloody champion!
I had no idea this was coming out, but I am sooooo glad that it is coming out and soon 
woooohooooo
HG- whats the 5th version? my memory is probably failing me again but I can only remember the 2 versions from the brewery One on barrels and the other clobering the bloke who spilt his beer,
then there is the one with gotrek and the white dwarf and the old one that was used in 4th ed that is still used now.
I like Thrott the Unclean.
Demented Skaven genetic engineers ftw, baby
long drong the pirate slayer. best ever!!!
Borgio the Besieger, took a hit from a cannon then crafts the ball into mace, class.
well in warhammer fantasy id say archaeon, mourgor, belakor, i cant decide
Nakai of the First Spawing
Basically one of the oldest mortal creatures in existance, who is a pain in the side for daemons
Come on...i have to keep up the scaley side! For if not me who will!
Lotl.
he survived the scavens plague. then he single handedly held a lizardman temple. when the relief force arived they found him surounded by hundreds of slaughtered scaven.
Konrad Curze? Hell yes! Besides him I'd say either Logan Grimnar or Boris, master of the bear cavalry!
For the coolest name, Amniach the Golden (alas, confined to a short filler story in some army book or WD article).
In game and probably overall, Nagash.
Dieter Helsnicht is also up there just because he was interesting and different.
Azhag the Slaughterer for me.
An animal of an orc semi-controlled by an ancient liche, and riding a Wyvern.
Malekith the Witch King.
Closely followed by Vlad von Carstein.
Although in gameplay I'm rather enjoying Mannfred at the moment...
Nagash, Malekith, Mazdimundi
and good old Richter Krueger
Nagash. If he were as powerful on the board as he is in the fluff, there wouldn't even be a contest.