I am a Tolkien geek. Let me take a stab.... (I'm going off the books a little more than the films, so forgive me)

Saruman - Engrishwebmaster. Surveys all from his lofty perch, commands hordes of minions, all under the horrible eye of the Dark Lord...

Sauron - President of EZ messageboards, of course. (sorry for the cast substitution, WG)

Gandalf - WinterGnat for his unlimited knowledge of lore and great wisdom

The Sleazy Deputy (Wormtongue, the traitorous advisor) - lurking around, checking out the ladies, whispering his own evil little plans into the king's ear, lust for power - I'm thinking Lord Fahruz. [nothing wrong with secret evil agendas]

Aragorn - HPF. Has the air of nobility, good to have on your side in a fight, doesn't suffer fools gladly.

Legolas - Percy Dovetonsils. Somewhat androgynous. Likes prancing about in forests in the nude.

Arwen - Manekineko. Gives comfort and wisdom to those who need it. Kicks ass when she needs to, but isn't dumb enough to go to war. Turkey slapping behavior is kept under wraps in Tolkien, but I'm sure she did it.

Gimli - Coffeebot. Don't underestimate this guy. Seems like he's just a funny guy who likes to eat and drink beer, but he's smarter than the lot of them. They just don't get it. They will man. Waxes poetic at odd moments.

Elrond - Dr. Superlove. Aloof. Many come from afar for his wisdom, he dispenses it to those he considers worthy.
   "Ah, the eternal refrain of humanity.  Please help me, I don't understand" - Pinhead, the Cenobyte