Kurzweil’s first novel, A Case of Curiosities, (Harcourt Brace Jovanovich, 1992), set in eighteenth-century France, was translated into thirteen languages and earned literary honors in England, Ireland, Italy, and France. The novel was reissued by Harvest Books in 2001.

His next novel, The Grand Complication (Hyperion, 2001), also translated widely, redirected the author’s love of invention to twentieth-century New York. The "grand complication" of the title is a 200-year-old timepiece commissioned for Marie Antoinette and stolen from a Jerusalem museum in 1983. To research the circumstances of the theft, Kurzweil spent nearly five years crisscrossing Europe and the Middle East, interviewing detectives, curators, collectors, horologists and watch dealers. Over the last two decades, devotion to the complicated passions of his characters has led Kurzweil to take courses in pop-up book design, study the repair of player-pianos and work behind the reference desk of a public library. He regularly constructs the contraptions "invented" by his characters. To date these devices have included roll-players, pocket-sized potato cannons, clocks and color wheels designed to distinguish different kinds of potato chips. A number of these inventions have been packaged into a science kit for children.

Since 2002, Kurzweil has been writing children’s books. He has published two novels in the bestselling "Leon" series: Leon and the Spitting Image (HarperCollins, 2003) followed by Leon and the Champion Chip (HarperCollins, 2005). Potato Chip Science (Workman, 2010) is an educational, eco-friendly science book and kit for children that comes packaged in a potato chip bag. Children use snack food related materials to learn about science in 29 experiments.

Allen has received fellowships from the Fulbright Foundation, the Guggenheim Foundation, the New York Public Library Center for Scholars & Writers, and the John Nicholas Brown Center for the Study of American Civilization at Brown University. He currently sits on the board of the Rhode Island Council for the Humanities and is a fellow at the John Carter Brown Library at Brown University. He lives in Providence, Rhode Island with his wife and son.