Do you guys remember mood rings? There was a period in high-school where I was obsessed with rings ... I wore one on every finger and one of them was a mood ring (and a ring watch ... do you remember those?). Unfortunately, I am one of those people whose hands are just perpetually on the cool side so my mood ring rarely changed colors.
When I found some mood beads, I instantly thought ... necklaces! They are made with thermo-sensitive material which means as your body temperature changes through out the day, so will the color of the bead. I haven't taken mine off since I made it. It is so fun to see the colors change through out the day (since my chest isn't as cold-blooded as my hands, it actually does change colors quite a bit!).