Also known as "deadheads", partially submerged snags posed hazards to early riverboat navigation and commerce. Colin Buchanan has narrated several Reginald Hill audio books, including "Deadheads" and "Exit Lines". Like Deadheads, members of Wharf Rats come from all walks of life. It became a movie about a series of concerts and the crew and the Deadheads. The Grateful Dead inspired thousands of self-proclaimed Deadheads. In 2008 he performed in the two Deadheads for Obama concerts. The sketches conclude with the band answering more questions from Deadheads. The event draws thousands of residents and Deadheads annually. The result was a greater readership and many angry Deadheads. These fans (who were known as "Deadheads") developed a sense of community and loyalty. This allowed many Deadheads a way to follow the band on its tours. "DeadHeads" premiered at the Newport Beach Film Festival on April 29, 2011. Next, all six members of the band answer pre-recorded questions from Deadheads. Fans and enthusiasts of the band are commonly referred to as Deadheads. Deadheads developed their own idioms and slang.