undoubtedbly one of the most noticeable actors with accents as he almost never is in roles where he has to disguise his British lilt, with the exception of a role like the one he had in "Road to Perdition." This British accent tends to define him and the roles he plays.
One of the best actresses in Hollywood, Kate Winslet actually has an accent, though most of her "Titanic" and "Little Children" fans forget this. This is due to how versatile Winslet is in all the roles she plays, flawlessly transitioning from American to foreign characters.
Bale is one of the biggest actors in the world right now and until you hear him in interviews off-screen, you always forget he has an incredibly thick accent. How often do you think about Batman being Welsh?
Bellucci in the states soon.
Penelope Cruz qualifies as one of the most noticeable actors with an accent, as she is gorgeous and talented in all her roles as a beautiful foreign fox. Chances are, she won't play anything else soon.
Daniel Day Lewis.
Arguably the best actor in the business, Daniel Day Lewis always has a different accent in each film he takes on. In truth, he is Irish, making his role as a revolutionary for "In the Name of the Father" one of his few parts where he wasn't creating a new voice. Soon he will perfect his American midwestern accent when he plays Abe Lincoln.
Dark Knight Rises," Tom Hardy is becoming one of the most noticeable actors with an accent out there. He will probably be acting with and without the accent for many years to come in the near future.