If stabbing your prey simply isn't enough for you, check out the WASP Injector Knife. Designed for taking out large land and sea predators, this hardcore weapon features a 5.25-inch blade and can hold up to a 24g gas canister, which is used to inject a freezing cold, basketball-sized ball of compressed gas into whatever you've punctured, dropping even the largest of monsters simply and effectively.
Nevermind that it collapses down to fit into an included OGIO pack for travel — the biggest trick the Trak Kayak ($4,900) performs comes after it's put together. Using three hydraulic jacks, the Trak can add or reduce tension on its skin to allow you to shape the boat to your needs. Need maximum speed? Make it lie flat. Extra maneuverability? Bow the ends up. It can even bend left or right to combat crosswinds. Like a Transformer, but without the awesome alien weaponry. [via]