The process used to locate a nerd within a reasonable proximity by sending a text, email or other type of social media message. The sound alert you hear is almost always associated with a video game sound or music. This is most effective in a home or office setting.
"Hey do you know where Matt is?"
"I not sure. Have you tried Nerd Echolocation yet?"
"Let me see here. I will sent him a text and tweet" click click click
"Oh, he is in the break room. I just heard the Mario 1-UP sound and Legend of Zelda theme song come from that direction."