Portal Easter Egg - The Big Bad Jellyfish

After escaping from the test chambers, you will eventually meet the rocket turret for the first time. Just before you do there will be a room in the hallway leading to the rocket turret. It will have two monitors (if you have commentary on it's the room where the voice of GLaDOUS talks about how GLaDOUS is sarcastic) just to the right of the monitors there is a drawing on the wall of what appears to be a jellyfish. Under the jellyfish it says "BIG BAD JELLYFISH WANTED." This may be a future 'boss'(this is just a thought and is entirely unoffical) in the Boreallis in Half-Life Two Episode Three which requires the usage of the portal gun once inside the ship.