Over the years, I've read far more books on leadership than I can count. To be honest, most of these books stick with a tried-and-true formula that doesn't stray too far outside the norm. For example, pick up any book on leadership, and you're sure to read about empowerment and teamwork and inspiring creativity.

But guess what? Highly successful leaders don't always stick with the advice repeated over and over again in these leadership books. In fact, they often have weird habits that help them get things done. Here are some of the most interesting.

1. Mark Zuckerberg: yearly resolutions

Facebook founder Mark Zuckerberg sets tests of discipline for himself each year. In 2009 his challenge was to wear a tie to work each day, and in 2011 it was to personally kill any animal he ate. This year's challenge is to read a new book every two weeks.

2. Steve Jobs: foodie

Steve Jobs was famous for eating only one type of food for weeks at a time. He once became so convinced of the virtues of eating carrots that his skin was reported to have turned orange from eating so many of them in a short period of time.

3. Marissa Mayer: micromanager

Marissa Mayer, CEO of Yahoo, is reported to personally approve every new hire in her company of more than 12,500 employees.

4. Mark Parker: brain balancer

Nike CEO Mark Parker has a notebook that he uses to keep the two sides of his brain balanced. While one page in the notebook is devoted to business brainstorming, the opposite page is used for sketches.

5. Donald Trump: germophobe

According to reports, real estate developer Donald Trump has a phobia for germs. He avoids shaking hands with the people he meets, he will not touch an elevator button, and he once passed out bottles of hand sanitizer to reporters at a press conference.

6. Bill Gates: rocker

Former Microsoft CEO Bill Gates was known for rocking in his chair during business meetings. The more excited he was (in a good or bad way), the more he rocked.

7. Jeff Bezos: memo writer

Amazon CEO Jeff Bezos requires senior executives to draft six-page memos in advance of meetings. These memos are then read in silence during the first 30 minutes of every senior executive meeting.

8. Henry Ford: weed eater

Ford Motor Company founder Henry Ford reportedly savored sandwiches made from "roadside greens"--weeds grown in his yard.

9. Martha Stewart: demanding boss

Martha Stewart is reported to allow only red or black ink to be used in her offices, and that employee desks be completely clear at the end of each business day.