Mobile VW Location via real world location
As efforts develop to overlay portions of the virtual world onto the real world (a concept called dual reality), we can use location sensing feature of mobile phone to place ones avatar in the virtual world.
Bob walks into a real Starbucks that is mirrored in the virtual world. His cell phone can sense his physical location thru base station triangulation or GPS. This information can be used to locate his avatar in the virtual Starbucks mirroring the real life location.