The excellent old school role-playing game Pits & Perils (by James and Robyn George) is now available as a hardcover book entitled The Collected Pits & Perils. Read "The Collected Pits & Perils... Is Here!" in Pits Perilous for more information on this minimalist retro-gaming masterpiece.
NB: The various Pits & Perils PDFs by Olde House Rules are available at DriveThruRPG.