Harold Perrineau on his story this year (spoilers up to S4 finale)

[KLOEN]

Yeah, I recognized a couple of actors as well.

Locke - Star Trek, Alias and JAG.
Michael - Oz
Eko - Oz
Charlie - Lord of the Rings
Jack - Party of Five
Claire - Roswell
Jin - Angel
Ana-Lucia - The Fast and the Furious
Richard - The Tick
Charles Widmore - The O.C.

With all these characters I immediately thought of their performance in the show or movie I've mentioned, the first time I saw them on screen in Lost.
Funny thing with the guy playing Charles Widmore.. His roles on Ugly Betty, The O.C. and Lost all have a lot in common with him being a rich and seemingly omnipotent kind of hard old-school man.
On Party of Five Matthew Fox also played the responsibility-burdened leader who got that job thrust upon him.
In LoTR Dominic Monaghan's role shared some goofball characteristics with Charlie in my opinion.
Michelle Rodriquez was exactly the same "take no crap, tired of everyone" in The Fast and the Furious as in Lost. Except now as a cop.

 

[biotech]

I remember Richard most from suddenly Susan.

 

[Agent Richard07]

To me, Terry O'Quinn will always be Howard Hughes from The Rocketeer.

 

[biotech]

Yeah, that was the roll I remembered him from the most, although I recognised him from Millenium, and the x files movie too, in fact once you start recognising a genre actor, you usually start seeing them all over the place.

 

[Mr Light]

I just thought of another wasted opportunity. Michael never went back to the Island! He spent on the whole damn season on the boat!

Not to mention that only a handful of characters knew he was back.

 

[biotech]

Well parts of him probably made it back.