Sheilas’ Wheels, a UK car insurance company for women designed convertible high heels that should make driving safer.

The Sheila Driving Heel tucks up into the shoe and the result is a flat shoe.
The concept is similar to those roller shoes, where you can release wheels from the sole.
The motivation for the insurance company to come up with this convertible high heels concept is the fact that 10% of female UK drivers report that they had a car accident or a near-miss because of wrong footwear. The survey about the Sheila Driving Heel currently indicates that 90% of people liking the idea. So maybe is jumping on the idea and actually produces these shoes.
More details on the I Love Sheilas Wheels fansite. (Thanks Cerstin).