Candles - Make scented candles. Melt wax in a double boiler. Add scents (from a candle shop) and old crayons for color. Put the wick in the bottom of each egg cup. Tie on a small washer to keep it on the bottom. Pour in the wax, holding up the wick. After wax has set, remove the eggcup.
Christmas Decoration Storage - Line cups with cotton, foam, or tissue paper and store small Christmas tree bulbs and ornaments in each cup.
Palette - Use the Styrofoam kind for watercolor or acrylic paints. Detach top of carton and use for mixing colors.
Cheap Ice Cube Trays - Use plastic egg cartons to make extra ice.
Money Container - Use old egg cartons to store your change for garage and yard sales. Egg cartons are good for this because you can separate all the change and it is easy to get to.