In 2006, Reznor played his first "solo" shows at Neil Young's annual Bridge School Benefit. Backed by a four piece string section, he performed stripped-down versions of many Nine Inch Nails songs. Reznor featured on El-P's 2007 album "I'll Sleep When You're Dead", providing guest vocals on "Flyentology". Reznor co-produced Saul Williams' 2007 album "The Inevitable Rise and Liberation of NiggyTardust!" after Williams toured with Nine Inch Nails in 2005 and 2006. Reznor convinced Williams to release the album as a free download, while giving fans the option of paying $5 for higher quality files, or downloading all of the songs at a lower quality for free. Reznor was also credited as "Musical Consultant" on the 2004 film "Man on Fire". The movie features six Nine Inch Nails songs.