Vasectomies are a great form of birth control, but the downside is that they're hard to reverse. Now researchers in Australia have come up with a penis implant that could control sperm flow at the flick of a switch. Operated via remote control, the implant would act as a sort of valve, blocking sperm sometimes and letting them through when you want. Of course, this could lead to some serious fights over who gets the remote control.
According to New Scientist:
The device is placed inside the vas deferens - the duct which carries sperm from each testicle to the penis. When closed, it blocks the flow of sperm cells, allowing them to pass again when it is opened via a remote control. The valve could be a switchable alternative to vasectomy, the researchers say . . . The silicone-polymer valve can be flipped between open and closed positions with a pulse of radio waves. A set of conducting "fingers" on the valve act as antennae and convert the signal's energy into sound waves that travel through the polymer and create stresses inside the device.
Radio-controlled sperm tap [New Scientist]