While studying business management at Yale University, Fred Smith nearly received a failing grade on a major business assignment. Convinced of the viability of his proposal, however, Smith vowed to pursue it upon his return from the Vietnam war.

The idea? That parcels could be delivered overnight at a profit using a private airline system with a centralised hub. The resulting company? Federal Express.

["The concept is interesting and well-formed," Smith was told, "but in order to earn better than a 'C,' the idea must be feasible."]

[Among a host of other ideas which were once deemed ridiculous:
* Godfrey Hounsfield was told a "CAT scanner" was "impractical."
* Sony Chairman Masaru Ibuka was told that a recorder with no speaker or recorder (ie. the Sony Walkman) was "crazy."
* Other shoe companies thought Bill Bowerman's brainstorm ('What if I poured rubber into a waffle iron?') was a "really stupid idea."]