I've been catching up with some manga lately, and stumbled across an interesting item in the fourth volume of "A Certain Scientific Railgun". Our heroine, Mikoto Misaka, a girl with the power to control electricity, is trying to track down information on a strange student. As it turns out, she uses a fairly interesting device to do this...

(This manga came out in 2009. But, an anime covering this volume is just starting broadcast this month. I'll be interested to see if her little device gets changed...)