AK-47: Familiar to us all, the Avtomat Kalashnikova is easy to fabricate and use. Designed by Mikhail Timofeyevich Kalashnikov in the 1940s, this weapon is arguably the most popular weapon in history. Apparently, you can bury a crate of AK-47s deep in the ground (properly protected, of course), dig them up decades later and they still will fire perfectly and jam rarely, if ever. That’s what makes this weapon the favoured tool of terrorists, insurgents, and desert fighters worldwide. Apparently the inventor was so horrified by the devastation and death caused by his brainchild that he regrets it ever being conceived.