Pillars of the Earth...

To quote Ken Follet, author of Pillars of the Earth-"...when things are simple, fewer mistakes are made. The most expensive part of a building is the mistakes"
The Minoan columns at Knossos were fairly simple in design, they did, however, reject tradition and reversed the equation making them smaller at the bottom and wider at the top to create the illusion of height.

The beautiful marble columns adorning St. Mark's Basilica in Venice were still fairly simple, they brought in variety by using marbles from all over the eastern Mediterranean and added elaborately carved capitols.

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Throw some artisans into the equation and Ornamentation began to enter the scene.
The Duomo di Orvieto is an exuberant example of motif and carved ornamentation including the use of  rococo  based solomonic columns.

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These carved columns from the Monreale Cathedral in Sicily are reminiscent of the moorish columns at Alhambra.

The next evolution of the column came through the introduction of caryatids.  Caryatid is defined as a support taking the place of a column. They began as female figures but later evolved to mythological supports.

"Proportion is the heart of beauty"-another quote from Pillars of the Earth and caryatids provided pleasing proportion to the exteriors of buildings.

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Michael Hansmeyer has done some modern tweeks on the simple column using math to create beauty.

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"Michael Hansmeyer is an architect and programmer who explores the use of algorithms and computation to generate architectural form. He is currently based in the CAAD group at ETH's architecture department in Zurich. He holds a MBA degree from Insead Fontainbleau as well as a Master of Architecture degree from Columbia University. He previously worked with McKinsey & Company, J.P Morgan, and at Herzog & de Meuron architects."(source)

Math and art once again, provide the pleasing proportion that Follet wrote about. Simple or adorned, these pillars of the earth are all works of art!