Wireless connections are everywhere now. Perhaps you're listening to us through your smartphone or laptop, or maybe you have one of those new-fangled smart fridges connected to the internet. Technologists now talk about the "internet of things", where objects around us are all connected up using wireless radio technology, and the potential applications are wide-reaching, from labelling banknotes to tiny bio-sensors for monitoring health. But one limiting factor is the size of the radio transmitter - a problem that may have now been solved by engineers in California. They've developed a miniaturised radio device - roughly the size of an ant - that sits on a silicon chip.