Josh Kaufman has a very interesting concept called The Personal MBA. It is available as a PDF-file over at ChangeThis. The introduction goes like this:
Business schools don’t have a monopoly on worldly wisdom. If you care more about increasing your effectiveness at work than a diploma and a few lines on your resume, the Personal MBA is for you.

It is a list of recommended books covering many business topics:
+ A Quick Note On Organization
+ Manage Your Life and Work
+ Learn the Fundamentals
+ Strategic Thinking
+ The Only Thing Constant is Change
+ Masters of Management
+ The Finest Minds in Business
+ Dollars on the Books (Finance and Accounting)
+ Numbers and Negotiations
+ Operational Effectiveness
+ Form and Function
+ Project Management and Marketing
+ Do Your Own Thing
+ Speak Your Mind
+ The Delicate Art of Human Relations
+ Sell, Sell, Sell!
+ Economics and Worldviews
+ Business, Past and Present
+ Rules and Morals
+ Analyze This
+ Voices of Experience

There is in all 42 books, lots of reading but it can be done while attending “school of life”. Mixing studies with practice makes learning easier. The catch is you will not get a MBA diploma.