Is there a name for that kind of actor described in the title of this thread?
2 actors come to mind that I had to look up on IMDB because I see them alot…Larry Miller and Clifton Powell.
You may not know who they are but most likely you have seen them in a movie you like.
Usually they are referred to as “character actors.” An actor who does that can have a long career in bit parts.
The champion is Charles Lane: 254 movies and 94 TV guest appearance in the IMDB. Recently celebrated his 100th birthday and was still acting at age 90.
In my circle of friends it was always “That guy,” as in: “Hey, it’s That guy!”
Reading threads here and elsewhere, I’ve found that this term is extremely common.
Go over to www.fametracker.com and click on “Hey! It’s that Guy!” They do write-ups of character actors. Lots of fun.
And Larry Miller is definitely one of my personal HITGs. I used to get him mixed up with John Carroll Lynch (another HITG), but I have it figured out now. 
Fametracker has an entire section devoted to this, named after, of course, the ultimate That Guy, JT Walsh.
I’ll see your JT Walsh and raise you a James Hampton.
And an additional challenge- name the Lucas Black film in which they both appeared.
Lucas Black, you know- that kid. 
You’re probably not heard of most of the top 10 most prolific actors and actresses, as ranked in the Internet Movie Database:
Actors
Actresses
Sling Blade (1996)
While I admire your research skills, you dare to mention America’s Sweetheart in a thread about “not famous” performers?!
What A Character is another good place to check out.
And if you know whats good for you, you’ll apologize to Eve for that comment about Mary Pickford*.
*America’s Sweetheart… but born in Canada
No need to apologize to me, but I’d be terrified of the ghost of Charlotte Pickford whuppin’ your ass!
Jeffery Jones (aka Jeff Jones) comes to mind. He just can’t seem to get that huge defining role…he’s got some great roles under his belt, but he’s firmly embedded as a character actor…cursed or blessed?
Stephen Tobolowsky, who is even the subject of a documentary, Stephen Tobolowsky’s Birthday Party. He played Ned Ryerson, the insurance salesman in Groundhog Day.
I like David Morse.
How about David Strathairn? I always figured he never got famous because nobody knew how to pronounce (or spell) his last name. I really felt bad for him when he got third billing in The River Wild because he HAD to know it was the peak of his career…and still, that bratty kid Joey Mazzello out-billed him!
Another guy who’s been in a million things and everyone would recognize but few be able to name is Brad Dourif. I think he’s just now starting to get some recognition for his role as the doctor on Deadwood but he’s been solid for years.
Just watched the remake of “The Manchurian Candidate” last night and saw Charles Napier in there. Another one of “those guys”…
I remember watching the extras on the Lord of the Rings DVD and in a bit where they talked about the actors in the film I thought they mentioned that Brad Dourif hadn’t been doing much film over the years.
(Looking at his IMDB listing I see that I might have got a mistaken impression. He’s in 89 films over 30 years and it looks like the films are equally spread among the years. Many of them I don’t recognize, but plenty of them seem pretty famous.)
Phillip Seymour Hoffman
But he is finally getting his name out.