Nature abhors a vacuum, or so the saying goes, and you can use that to your advantage when it comes to building a giant table-sized cannon that can obliterate a watermelon without the need for dangerous explosives or compressed air tanks.
Still pumping your watermelons full of vodka? What is this, summer camp? You're in the real world now, it's time for an adult solution to your fruit-based adult beverage storage needs. Maybe one that even involves a spigot.