Christina,
The power of a shower is so common, that a company created "Aqua Notes" for people to capture their thoughts in the shower.  No joke.  I am a Shower Thinker and own the these little gems of shower productivity.  Http://twitter.com/showerthinker to find their powerful shower! :)

You ask, what type of mental shower can we create throughout the day?  For me, I can now get a mental shower anywhere by pausing -- just for a minute -- and asking focusing on one or two words.  I silently ask myself "what goes with these words" and the mental shower starts to flow.

Unique post with great insight for all.

Many thanks,
Kate