Usually stated when realizing you are completely fucked and are about to be killed or be mortally wounded. Also used when someone has fucked up and is about to blow themselves or something important to kingdom come.
Guy: *plants a bomb on the building* Wait...that's OUR building! OH SHI- *Insert generic massive explosion here*
Short of "Command and Conquer" a popular RTS Series. Originally the FIRST EVERY RTS, Its grown since then under the parentage of "Westwood Studios" which was later taken over by "EA". The series has begun to become lackluster under EA.