Sneak peek: Woodstock on Dateline

To commemorate the 40th anniversary of the legendary music festival that defined a generation, Dateline NBC examines people whose lives were altered by Woodstock. See it Friday at 9 p.m. ET, 8 p.m. CT on NBC. (Dateline NBC)

MSNBC | August 6, 2009

Tags:. .dateline. .woodstock. .peek. .sneak