The Finnish company has filed a patent for the idea of tattooing, stamping or spraying ferromagnetic material on skin, which would be connected to a mobile phone. The tattoo could vibrate for any kind of alert, from a top-up to an answer phone message. Options that where would it cover suggested so far are a personís arm, abdominal area, finger or fingernail. People might get charged up about the possibility of using the tattoo as an identity check and as a password to use devices such as laptops. But for those who like to relax and switch off, the idea may need to be put on hold.