Melted Bead key chain - Place plastic beads in a single layer in a muffin tin, leave space for a hole (or you can drill one later). Heat at 400 degrees for about 30 minutes. Could also make as a charm for a necklace?
Pony Beads & Baking Paper. Place the beads in close shapes on baking paper/bake in oven at 425F ~10 min. (since the fumes are probably toxic, I'd try a heat gun). The beads also melts with different speed, so keep a close eye on oven at all times. Then cool. Use as desired.