I believe that the most powerful corporate values statements are those that start with a verb. Here are two examples:

Zappos

• Deliver WOW Through Service.
• Embrace and Drive Change.
• Create Fun and a Little Weirdness.
• Be Adventurous, Creative and Open-Minded.
• Pursue Growth and Learning.
• Build Open and Honest Relationships With Communication.
• Build a Positive Team and Family Spirit.
• Do More With Less.
• Be Passionate and Determined.
• Be Humble.

AWeber

• Foster Respect and Cooperation.
• Listen to What People Say About Us. Invite Feedback.
• Learn. Educate. Innovate.
• Don’t Take Ourselves Too Seriously; Have Fun.
• Create Remarkable Experiences.

Source: http://yfsmagazine.com/2013/02/01/company-culture-an-inside-look-at-100-core-values-from-15-winning-companies/