According to Wired Magazine, the best thing the boss of a creative team (like advertising, programming, engineering, or so on) can do to promote their creative talents is to let them goof off on facebook or twitter for a while. Wait, what?
It seems that creative works are caused by a sort of cognitive collision, when two of your ideas ram headfirst into each other, leaving the debris of a new idea behind. People notice things, incorporate them into their existing ideas, and when two of them collide, bam, awesome new idea.
This explains why it's so much harder for me to come up with new ideas to write about now that I've graduated. College did involve going to a different environment, with shiny new ideas constantly inserted into my conciousness where they collided with existing ones. The constant need for task switching helped too. Now that it's over, thinking "Hmm, need job, find find find okay now tired watch television" all day isn't as helpful a mode.
The article warns that it's not sufficient to just goof off. A game of solitaire might help you feel better after a hard day, but it's not going to give you any new ideas. You need novel stimulation of brand new information for this to work. Even if this information is completely irrelevant to your problem.