When I was in college my father and I had a jewelry business. We cut stones, ground cabochons, and cast settings in silver and gold using the lost wax technique. In the upper corner of the first box are the testing needles we used, along with a touchstone, to test the karat of gold samples.
I also love the beach, and so I have seashells scattered all over my house, including over the top of my shadow boxes.
At the very end are crow feathers I've collected. I use them to paint marble veining and other textures.
Everything is handy, useful, or inspiring. I think you have to surround yourself with things you love or that give happy memories. They all help you to be creative.