"Memories are Here to Stay" by The Intruders for the vocal sample.
Trivia
"Ghostwriter" was featured in a 2005 UK TV advertisement for Anadin Extra, as well as in the opening credits to the 2004 romantic comedy Wimbledon and 2005 romantic comedy Prime. In America it is featured in advertisements for Wells Fargo bank.
"Smoke and Mirrors" was featured in the 2004 Skate Video "Paul Rodriguez's Forecast" in which the track was used in Paul Rodriguez's part.
Early copies included a "hidden" song on the same track as "Work," titled "Here's What's Left." A slow, wistful track making use of sampled vocals, much like "Smoke and Mirrors". Def Jux was forced to drop it from later pressings due to a sample clearance problem.