“Twenty percent” time

Source of information: http://en.wikipedia.org/wiki/Google

All Google engineers are encouraged to spend 20% of their work time (one day per week) on projects that interest them. Some of Google's newer services, such as Gmail, Google News, Orkut, and AdSense originated from these independent endeavors. In a talk at Stanford University, Marissa Mayer, Google's Vice President of Search Products and User Experience, stated that her analysis showed that half of the new product launches originated from the 20% time.

Can this work in every company?