A lot of people fear that drones might invade their privacy (and for good reason), but put to good use, UAVs can help monitor crops, film spectacular aerial views and, in this case, capture tax-evading millionaires. Law enforcement agencies in South America have been using drones widely to aid in their investigations, such as finding drug smuggling routes. So, when they suspected that some properties registered as empty lots in a wealthy Buenos Aires area aren't exactly "empty," they dispatched some of their $10,000 drones equipped with cameras to take pictures of the properties. As you might have guessed, instead of coming up with pictures of dirt and overgrown bushes, the UAVs took home snapshots of huge mansions replete with swimming pools. The homeowners are now facing some serious fines, and the government expects to earn roughly $2 million in taxes from the hidden mansions.