When you want to track your health, you’d usually have to shell out for a wearable that you have to have on you for it to work. However, what if someone could read your heart rate using wireless technology? It sounds like something out of science fiction, but a team of researchers believes it’s not as far-fetched as you may believe. They’ve published a paper claiming that, not only can Wi-Fi signals help detect heart rates with extremely good accuracy, but you can achieve these results with a super-cheap Raspberry Pi Wi-Fi chip.