During the introduction sequence for the mission where you are about to land on Rannoch,
Commander Shepard is standing in the Normandy's bridge talking to Joker about the fact 
that there sure a lot of enemies out there. Joker laughs it off and says that with the 
Normandy's stealth drive engaged, the only way for the Geth to notice you is if you all
start singing the Russian national anthem. This is a direct reference to the 1990 film, 
The Hunt For Red October.