One item on my “12 before 2012” is to “Create Evidence pages when you get new materials”. According to iHanna blog, an evidence page is a page in your Art Journal or notebook where you break out new stuff.
My first thought is my collection of washi tapes aka Japanese masking tapes, which I grouped them according to their manufacturers, in a notebook from a dear friend.
It is a way to keep them for myself, as “evidence” that I once have them. When they are all used up and gone one day I can look back at the page and remember.
I also take time to recall where I bought these washi tapes as I first bought most in Japan in 2008. These evoke happy memories of my various Japan trips in different places and seasons.