Well, there was one glitch I heard about spy if a mercenary glitches you when you try to pull him over, press start and A repeatedly and you can pull him over. The moves might not be successful though.
QUOTE(Naborneo @ Mar 28 2006, 04:07 PM)

Easter Egg: Fish
Areas: Aquarius | Mode: All | Person: 2 Spy’s | Equipment: None
1. Have both Spy’s make their way to the Pirate Room.
2. In the Pirate room go to the landing between the stairs going to the upper and lower lever of the Pirate room.
3. Towards the back corner there should be a spot to perform a team action.
a. (Back corner if your looking at the wall, to the right)
4. Perform the Team Action and toss one of the Spy’s up to an invisible ledge.
a. (You only need one Spy up there)
5. Have the Spy Climb up on the invisible ledge and stand up.
6. After a few moments you should now start to hear bubbles.
7. If this is done correctly when you look around the Pirate Room and you should see Fish swimming in the Pirate Room.
Also, you can stand on the invisible ledge and toggle the fish on and off by jumping in that spot.