The Fridge and Deep Freeze are the places you store ready and long-term reference.  The Fridge contains things that deal with currently active projects.  In terms of paper, it is usually a file drawer with file folders labeled for each project.  The Deep Freeze is where you keep reference materials on non-active stuff - usually another file folder.  In electronic terms, Evernote is an awesome (and free) way to hold onto both your active and non-active reference.  On the Mac, Yojimbo is another popular product.

My Implementation

I have two file drawers, one as a Fridge and a much larger one for my Deep Freeze.  These days, I'm much more paperless, as I invested in a Fujitsu scanner which I use in combination with Evernote.  If you do not use Evernote, I really can't stress how awesome it is in implementing File and Forget.  It also integrates with several Master Planners.

Secondary Principles this Tool Implements

  1. Deal With It Now
  2. File and Forget