Found this great manifesto on ChangeThis. It lists 40 books, self study of which, claims the author, could provide one with most of the benefits of an MBA degree - all without the lost wages for a couple of years, and the prohibitive (In US) course fees.
A lot more useful information is available in the end notes of the pdf.
It does seem like a great concept, and a good option for people who do not want a complete change of vocation, or who are indifferent to the exceptional starting salaries which a full time MBA provides - albeit to the chosen few.