The original Spock/Spock Prime (played by Nimoy) has now been in more Trek films than any other character in the Star Trek universe. Earned him a spot on my Actors With Frequently Recurring Roles quiz. RDJ almost made it for playing Iron Man, but so far he's only played good ol' Shell Head a total of 6 times, and I had to make the cut off 7 to keep the quiz a reasonable size. If he shows up in Avengers 2 then I'll update it.
Also Danny Ocean and OB1 make an appearance on my characters played by multiple actors quiz linked to in the comments of the above.
Manhunter - Brian Cox
Silence the lambs - Anthony Hopkins
Hannibal - Anthony Hopkins
Red Dragon - Anthony Hopkins
Hannibal Rising - Gaspard Ulliel
Hannibal Rising - Aaran Thomas (Hannibal as a child)
Tv series Hannibal - Mads Mikkelsen