i think the box concept is pretty common. old-T mentioned he did it with certain clients, and austin-t tells me he has a box for some clients also.
both of them do CBT. old-t also did humanistic therapy, austin-t does object relations. i think they've both had clients physically write things down and leave it in the box to look at the next time they're in. i.e., more than just visual imagery.
pdoc is a pdoc (

) i.e., minimal therapy training, but i've given him a letter once which i know he keeps away from my file and which we're only allowed to speak about when we both have it in front of us. he keeps it with his "happy things" and tells me he does it to keep me safe. sometimes he'll open the drawer (which he keeps locked) and show me the new things he's added to his drawer, so i know he's got things in there keeping my 'stuff' company.