Buddy Spy allows you to keep track of what other Yahoo Messenger! users are doing, even if they are in Invisible or Stealth Mode.
Buddy Spy shows if the user is online, what chat room they are in (if any) and if their web cam is online. Buddy Spy is able to do this by connecting to Yahoo! Messengers servers and using its YMSG protocol.
Buddy Spys Feature list includes: Stealth Checking, Room Checking, Webcam Checking.