Eighteen times the Hugo and Nebula voters have agreed on what was the best science fiction or fantasy novel of the year. They were:
Dune by Frank Herbert
The Left Hand of Darkness by Ursula K. Le Guin
Ringworld by Larry Niven
The Gods Themselves by Isaac Asimov
Rendezvous with Rama by Arthur C. Clarke
The Dispossessed by Ursula K. Le Guin
The Forever War by Joe Haldeman
Gateway by Frederik Pohl
Dreamsnake by Vonda McIntyre
The Fountains of Paradise by Arthur C. Clarke
Startide Rising by David Brin
Neuromancer by William Gibson
Ender's Game by Orson Scott Card
Doomsday Book by Connie Willis
Forever Peace by Joe Haldeman
American Gods by Neil Gaiman
Paladin of Souls by Lois McMaster Bujold
The Yiddish Policemen's Union by Michael Chabon
That's more than 40% of the time they selected the same book. The time of the greatest agreement was the 1970's when just two years that decade they disagreed. The least agreement occurred in the 1990's where they only agreed twice.
Almost all of those books are worth checking out though I think Forever Peace should be avoided. I didn't like Paladin of Souls but fans of epic fantasy might find more to enjoy in it than I did.