Keith trotted at her side, a small, thin lad, in his white leather zip-up jacket, his jeans and black plastic shoes.

ECONOMIST: Winnie Johnson

While Crocs clogs were undeniably popular, they were also scorned by fashionistas and people tired of seeing the colorful plastic shoes nearly everywhere.

CNN: How a trendy shoe nearly lost its footing

Entrepreneurs transform discarded plastic into bags and shoes.

FORBES: Welcome To The Megacities Project

Shoes made of hard plastic may improve matters, especially as they can be glued rather than nailed on to hooves.

ECONOMIST: Veterinary technology

As I plugged my earphones into my iPod and flipped through some magazines, the woman who bought the Gucci shoes walked down the aisle, carrying many plastic bags of duty-free goods.

FORBES: Are Chinese Opening Their Wallets?

For those determined to take hygiene to a ridiculous level, Travel Feet are plastic feet covers that you can wear in airports when you have to take your shoes off for security.

ECONOMIST: Business travel