FILE - In this Jan. 13, 2007 file photo, actor Hal Holbrook greets patrons in stage make-up following his one man performance of 'Mark Twain Tonight' at the University of Texas at Tyler, Texas. His 56 years of one-man 'Mark Twain Tonight!' shows hit a milestone in Elmira, N.Y. on Wednesday, April 21, 2010, the centenary of the author's death. At 85, though, the Emmy Award-winning actor isn't sure how long he'll continue his famous channeling act. (AP Photo/Dr. Scott M. Lieberman, File)AP – Hal Holbrook has performed on stage as Mark Twain far longer than Twain himself did.