A microhistory is a history of something very specific. Here are some fun ones to choose from.
Salt: a world history by Mark Kurlansky
Bicycle: the history by David V. Herlihy
The Box: how the shipping container made the world smaller and the world economy bigger by Marc Levinson
Birth: the surprising history of how we are born by Tina Cassidy
Rain: a natural and cultural history by Cynthia Barnett
Consider the fork: a history of how we cook and eat by Bee Wilson
Butter: a rich history by Elaine Khosrova
Uncommon Grounds: the history of coffee and how it transformed our world by Mark Pendergrast
At Home: a short history of private life by Bill Bryson
Heart: a history by Sandeep Jauhar
Quackery: a brief history of the worst ways to cure everything by Lydia Kang
Cannibalism: a perfectly natural history by Bill Schutt
Holy Shit: a brief history of swearing by Melissa Mohr
The Golden Thread: how fabric changed history by Kassia St. Clair