There’s something new to add to your fun mental list of invisible internet dangers. Joining classic favorites like adware and spyware comes a new, tricky threat called “cryptojacking,” which secretly uses your laptop or mobile device to mine cryptocurrency when you visit an infected site. Malicious miners aren’t new in themselves, but cryptojacking has exploded in popularity over the past few weeks, because it offers a clever twist.

Get in-depth coverage of current and future trends in technology, and how they are shaping business, entertainment, communications, science, politics, and society.