As an admirer of Dourif's copious body of work, I really enjoy this 6-year-old thread on IMDB:

IMDb :: Boards :: Brad Dourif :: 6 Degrees of Brad Dourif (http://www.imdb.com/name/nm0000374/board/flat/14591119?p=1)

I'm not even halfway through it yet, but I just
wanted to point on an easier road to Bill Paxton.

From the IMDB discussion:

Bill Paxton was in A Simple Life with Briget Fonda
Briget Fonda was in Jackie BRown with Robert Deniro
Robert Deniro was in The Last Tycoon with Jack Nicholson
Jack Nicholson was in One Flew Over the Cuckoo's Nest with Brad Dourif

That was in 2005. Since then, there's a much faster way though:

Bill Paxton was in "Tombstone" with Powers Boothe
Powers Boothe was in HBO's "Deadwood" with Brad Dourif

Nya-ha!