The sky's the limit when it comes to what you can do with a versatile rotary tool. Etch glass or sand; carve wood, or use the tool for jewelry-making. A rotary tool is strong enough to cut through terra-cotta and precise enough to make an intricate pumpkin carving.
You'll find rotary tools at your local hardware store, and a kit comes with multiple tips and attachments. Depending on how big of a kit you need, you could spend $65 to $175.