The how-to instructions provided here are for the birdbath trellis. However, you can use these techniques to create a variety of designs. Add color by mixing dye into the concrete or by applying ceramic tiles to the basin. For the trellis, you can try other patterns, or use a ready-made trellis of wood or metal.
This project costs less than $50 if you can obtain scrap lumber and plywood for the concrete mold. If you have to buy the wood, double the cost. The nice thing about a mold is that you can use it more than once. Consider making several birdbaths for your friends.