TeamSpeak Overlay (TSO) is an Application designed to be use with TeamSpeak, that allows players to "see" who is speaking. With TSO, an addition to your games HUD allows you to see whos talking without having to switch out of the game.

TSO works by overlaying a list of the current speakers into the games window, over the top of the game thats running. It does this by directly hooking the DirectX or OpenGL APIs. It then "reads" the Teamspeak Window, to obtain the current speakers. It then draws this on top of the running game.