I thought of that while riding my bicycle. -- Albert Einstein (on the Theory of Relativity)

From JFK to John Lennon to Helen Keller, famous figures the world round have exalted the beauty of the bike since they first appeared in the 19th century. Now there are over 1 billion bikes in the world. That's one for every 6.8 people on the planet and two times the number of cars!

These humble, mostly peaceful vehicles are the source of much musing. Many great writers and thinkers, including Einstein, noted the joyful, expansive thoughts one often has while biking. There's something about being outdoors, doing light exercise and being alone with one's thoughts that inspires euphoria.

Artist Mario "nerosunero" Sughi explores biking's introspective powers in "Escape/Blue Landscape." Mario told me that he sees his chic biker in the midst of "crossing an abstract landscape both physically and mentally." She moves from chore to chore with shopping bags in tow and a mind buzzing with activity.