Among the pieces: his investigation into why there are so many different kinds of mustard but only one kind of ketchup; a surprising assessment of what makes for a safer automobile; a look at how we hire when we can't tell who's right for the job; an examination of machine built to predict hit movies; the reasons why homelessness might be easier to solve than manage; his famous profile of inventor and entrepreneur Ron Popeil; a look at why employers love personality tests; a dissection of Ivy League admissions and who gets in; the saga of the quest to invent the perfect cookie; and a look at hair dye and the hidden history of postwar America.