The cre­ation of 3M’s Scotch Tape, the Dec­la­ra­tion of Inde­pen­dence and Metal­lica: just three of the sto­ries Ben Cas­nocha retells to show the impor­tance of inno­va­tion through side projects.

Is giv­ing away a day a week of your employ­ees’ time worth it? Google exec­u­tives seem to think so. They cite first the enor­mous good­will gen­er­ated inter­nally: “20-percent time sends a strong mes­sage of trust to the engi­neers,” says Marissa Mayer, Google vice pres­i­dent of search prod­ucts and user expe­ri­ence. Then there is the actual prod­uct out­put which of late includes Google Sug­gest (auto-filled queries) and Orkut (a social net­work). In a speech a cou­ple of years ago, Mayer said about 50 per­cent of new Google prod­ucts got their start in 20 per­cent time.

Jack Hip­ple, a con­sul­tant who works with com­pa­nies on inno­va­tion, says cor­po­rate sup­port for employ­ees’ nat­ural curios­ity can lead to bet­ter new prod­uct ideas than tra­di­tional focus groups: “You have to have some vehi­cle for side-project time because senior man­agers or cus­tomers don’t know enough about the future to know what’s coming.”

Cas­nocha notes that not all com­pa­nies can offer side-project time, espe­cially startups:

There are too many essen­tial tasks that need to get done sim­ply to survive.

Tom Kin­n­ear, a pro­fes­sor of entre­pre­neur­ial stud­ies at the Uni­ver­sity of Michi­gan, says Google and 3M both could sup­port exper­i­ment­ing after their core prod­ucts became prof­itable: “At the out­set there are such tight mar­gins it’s hard to allow for side projects. The pres­sure from your investors to focus, focus, focus is just overwhelming.”