By Nicole Sperling
Updated February 05, 2010 at 11:55 PM EST

It’s really been the year of the documentary at this year’s Sundance Festival. Now Joan Rivers–A Piece of Work and The Tillman Story join the ranks of such docs as Davis Guggenheim’s Waiting for Superman and the uber-contemporary Catfish that won buyers quickly after screening at the festival. Joan Rivers–A Piece of Work, which examines the comedian’s private life and a rare look at her comedic process, was bought by IFC Films last night for mid-six figures. The film, from directors Ricki Stern and Annie Sundberg (The Devil Came on Horseback) will receive a 15-city theatrical roll-out sometime this summer.

And Harvey Weinstein made his second purchase of the Sundance festival nabbing The Tillman Story about Pat Tillman’s family’s crusade to uncover the truth about the death of this star football player turned military man who was killed by friendly fire in Afghanistan. Directed by Amir Bar-Lev (My Kid Could Paint That), the film attracted quite a few buyers.

Still likely to sell is Lucy Walker’s Countdown to Zero which focuses on the terrifying ease of which terrorists can get a hold of nuclear weaponry and Smash His Camera, which depicts the original paparazzo, Ran Galella.