I would also second the nomination of Audrey Niffenegger’s The Time Traveler’s Wife, which led to a very interesting discussion in our book club (which has now been meeting for almost eleven years). Some other favorites of ours, over the years:
The Perfect Storm by Sebastian Junger - gripping adventure and tragedy at sea
Last Chance to See by Douglas Adams and Mark Carwardine - a tragicomic travelogue about endangered species
In the Lake of the Woods by Tim O’Brien - a creepy, Vietnam-influenced mystery
The Hot Zone by Richard Preston - fascinating nonfiction about a near-outbreak of the Ebola virus in the U.S.
The Reader by Bernhard Schlink - quiet novel about love, guilt and betrayal
The Great Santini by Pat Conroy - novel about a domineering Marine and his family
Angela’s Ashes by Frank McCourt - deeply moving novel about growing up poor in Depression-era Ireland
Everybody Smokes in Hell by John Ridley - scabrously funny novel about a suicidal rock star and a beautiful assassin
My Dark Places by James Ellroy - nonfiction; the author investigates the murder of his own mother
Tuf Voyaging by George R.R. Martin - sf comic (!) novel about ecological engineering, overpopulation, absolute power and war
Fatherland by Robert Harris - chilling alt-history about a murder investigation in 1964 Nazi Germany
Into Thin Air by Jon Krakauer - true story of a Mount Everest climbing expedition gone horribly awry
Founding Brothers by Joseph Ellis - masterful, Pulitzer-winning history of the Framers and their dealings with each other
First Among Equals by Jeffrey Archer - an engrossing political novel, tracing the lives, loves and careers of three rising British politicians who eventually vie to become prime minister
The Killer Angels by Michael Shaara - another Pulitzer winner, a powerful novel about the Battle of Gettysburg
Everybody Smokes in Hell by John Ridley - scabrously funny novel about a suicidal rock star and a beautiful assassin
*
A Long Way Down* by Nick Hornby - comic novel about four would-be suicides who meet on a London rooftop
OK, I’ll stop now. Except to add… my wife’s book club read The Guernsey Literary and Potato Peel Pie Society and liked it very much; I haven’t read it.