This week, we take a look at the fascinating story of how Mikhail Kalashnikov's AK-47 assault rifle came to be the world's most popular firearm, with as many as 75 million units currently in service around the globe. Throw an AK-47 into a combat zone, and David suddenly starts beating Goliath - it's become a powerful political symbol of strength in the face of invasion or repression. It's the most successful killing machine in history, which is a horrifying achievement and obviously not something to be applauded, but with reference to its impact on humanity it is, sadly, among the greatest inventions of the 20th century. Also, Geoffrey Baird has been surfing away in his sound booth this week, and he's dug up 5 oddball gadgets for our weekly roundup.
Read the full article: Gizcast 7: Great Inventions - the AK-47