Grow sweet strawberry in a vertical PVC tube is great solution for small garden or yard. Vertical planter will save you a lot of space, at the same time keep plants out of reach from garden insect pests AND enable you to switch to hydroponics.
Erupting volcano - Most of the geodes that we find today were actually created when ancient Volcanoes erupted! As the lava cooled, air bubbles became trapped inside creating empty pockets. Over millions of years these pockets filled with the minerals