In the game of runescape (which is an MMORPG) there are certain areas where you can fight other players. If you are in a fight and teleport out. You are referred to as a teletubby. Meant to be an insult.
"O my god i was about to kill that guy and he teleported! Stupid tele tubby!"
A person who is usually getting beat in the wilderness of Runescape, and decides to teleport out of the wilderness.
PLayer A: * gets a 26 hit on him then teleports*
Player B: Stupid noob. What a tele tubby!