I'm currently reading Nevertheless: The Varieties and Shortcomings of Religious Pacifism by John Howard Yoder. It's a fascinating book, as I would expect from Yoder. Furthermore, the notes to the chapters often contain insights and illustrations as important and interesting as those in the chapters themselves.
Alas, the book has endnotes, not footnotes. This means that either I'd have to flip to the back of the book each time I reach a note marker (a tedious exercise), or I need to wait and read the notes for each chapter at the completion of each chapter (which sometimes separates a note from its chapter context), either way keeping a second bookmark for the notes. I choose the latter because it's easier, but certainly I wish I could easily glance at a footnote each time the author wishes to provide a note.
Let us all agree: footnotes are superior to endnotes.