I have one of those too!
Mine contains....
-a pink stone my T gave me,
-a goodbye letter my T wrote me,
-a mindfulness audio exercise reading that my T has done
-a little note with a reminder to "breathe" - written/doodled by a friend of mine.
-a bandage
-a red marker (for cravings of SI)
-a bracelet made a million years ago with some close friends,
-a little scrapbook a friend made me
-a cut-out heart that was given to me by a former T
-a couple of meaningful pictures
-a letter of recommendation written for me by an old professor
-my favourite candle that smells of vanilla (brings lots of positive associations)

Also Terry, I have a teddy bear with a stomach you can heat up too! it doesn't have a smell or anything, but sometimes when I'm sad, I warm it up and bring him to sleep with my to cuddle ... though technically I sleep with him every night, just not heated up every night