The Great Big Book of Mighty Machines by Ian Graham and Jean Coppendale
This book collects a half-dozen "vehicle" books under one cover. Each section groups together a set of vehicles (like cars), and provides a big picture and description of it on a page. The vehicles range from BMX bikes to mining dump trucks and all sorts of things in between. It is actually fairly readable, with a bit of progression through each section. However, it never tries to tell a narrative. The real purpose is pictures of all sorts of big machines. There are obvious "detail" sections for each vehicle that can double the length of the book - though it can easily be read without them.
Five year old boys love it.
