I think Scott Adams ( Author of Dlibert) should be included in this list. Though he is not traditional management Guru his charcters like Dilbert, Wally, Dilbert's boss,Asok teach many "true" things about corporate management. His style is humorous but contents are very serious. he is much better than many so-called goody goody management guru. Scott Adam's comic strips amuse and teach at the same time. Anyone in world who has spend some time in cubicle ( Term borrowed from Scott Adams ) can relate to Scott Adam's "management" books and comic strips