Warning: free hotel wifi is a hacker’s dream

Hotel systems are so leaky it's worth investing in your own virtual private network

You've just arrived at the hotel after a delayed flight and a half-hour wrangle with the car-hire firm. And then you remember that you've forgotten to pay last month's credit card bill, and there'll be an interest charge if you wait until you're back at base. But - hey! - you can do it online and help is at hand. The receptionist is welcoming and helpful. They have wifi and it's free. Relieved, you ask for the password. "Oh, you don't need one," he replies. "Just type in your room number and click the box."

Phew! Problem solved. Er, not necessarily. At this point the human race divides into two groups. Call them sheep and goats. Sheep are sweet, trusting folks who like to think well of their fellow humans. Surely that helpful receptionist would not knowingly offer a dangerous service. Also, they find digital technology baffling and intimidating. And they cannot imagine why anything they do online might be of interest to anyone.