Most mobile phones have Bluetooth which allows them to discover other Bluetooth devices in the near physical area. This discovery capability has enabled users to open communications between people who are in physical proximity with active bluetooth devices (called toothing).

Bob is in Starbucks and his avatar is in the virtual Starbucks. Bob notices that there are other avatar enable devices nearby. Bob can attempt to contact one to establish further communications.

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.

When a users mobile phone is connected to the internet, the users presence should be available to others.

Bob is away from his computer but has a mobile phone with IP connections. Bill who is in a virtual world or simply online, can see that his friend Bob is online and can contact him if desired.

Whether it is text or voice, both public and private communications are desired. Within a virtual world, communications can be established based on virtual proximity or thru a buddy list. As we move between VW's independently of the people we are in contact with, the communications channel should remain open.

A participant in a private conversation should have the option of handing off there side of the conversation to another client or device such as a mobile phone.

Bob is chatting with Bill in a virtual world. Bob needs to leave the virtual world, but Bill is staying. Bob can hand off his private conversation with Bill to his mobile phone as he leaves the virtual world.

Presence tells us if someone is online somewhere. Current IM systems maintain their own user registry and provide presence to registered users. As we move away from private solutions we need a service that provides online status regardless of whether the user has an IM client open, in a virtual world or on a mobile phone. The presence server does not release information about a user unless the user wishes it. The status information expands from just online status to include how to connect to the user no matter how they are connected.

Bob signs on to the internet. He wishes to contact his friend Mary who is on his buddy list but he does not know if or how she is connected. Mary may have a standard IM client open, she may have her cell phone on or she may be immersed in a virtual world. Bob finds her online status thru a common presence service, which can then notify Mary that Bob wishes to communicate with her. She can then (automatic if preferred) release information to Bob that will allow him to communicate with her.