During a recent long and particularly boring meeting I was sitting next to a laptop computer which was plugged in to a wall outlet. I used my magnetic sense to explore power supply, which emitted a now familiar buzz from the small transformer inside it. I was quite surprised to also feel a sensation from the power cable as well, a faint vibration but definitely there.
When current flows through a straight conductor, there is a magnetic field encircling it. In the case of a DC current the field is stable and the direction can be determined using the right hand rule.
Pretty cool, nonetheless.