"Work is not supposed to be fun" is one of the hoariest axioms in business. In The Levity Effect (Wiley, $22.95), bestselling author Adrian Gostick (The Carrot Principle) and humorist Scott Christopher take it on, explaining why it pays for entrepreneurs to laugh a little. The authors treat the topic seriously, including research and expert opinions to draw a correlation between lighthearted leadership and loyal employees, satisfied customers, and higher profits. It also offers ideas for fluffing up your company's mood.After more than two decades of telling entrepreneurs they were doing it all wrong, Michael E. Gerber has gone back to the beginning. With Awakening the Entrepreneur Within (Collins, $24.95), the dean of small-business gurus tells readers how to use the four dimensions of the entrepreneurial personality--dreamer, thinker, performer and leader--to inspire the vision and purpose to craft their own business narratives.