The frantic "Where r u?" text message has been shown the door, thanks to this revolutionary Facebook tool that gives suspicious partners an electronic map showing the location of their spouse.
The Social Network Integrated Friend Finder (Sniff) is a new application, accessed via Facebook or mobile phone.
The service, which is popular in Scandinavia, promises to provide users with a detailed map of their friends' locations, any time and anywhere.
"Sniffing" works through similar technology used by the police to track down suspected terrorists or missing children via their mobile phones. The phone sends a signal to nearby base stations.
Positioning software performs a triangulation calculation on the information from the base stations and converts it into a geographical location.
"Privacy is paramount and sniffing should only be used by people you can trust. It is a fun way to solve the proven most popular text message, 'Where r u?'" Times Online quoted Brian Levin, chief executive officer of Useful Networks, as saying.
Travellers who find themselves lost in a new city could also make use of the service.
"You can 'sniff' yourself if you really need to," Levin said.
But employees who are enjoying a long lunch or a secret liaison instead of the business meeting in their diary could also find themselves "sniffed out".
Levin said: "If the employer is paying the phone bill and employees are aware they can be 'sniffed', at least everyone knows those are the rules."
However, he cautioned that sniffing should not be relied upon by parents to track their young children, as the service will only place a location within a radius of about 200m (650ft).