"Time and tide wait for none." Trick your brain into thinking, it does!

Greater attention leads to a perception of a longer period of time. When you are hearing our favorite soundtrack, our senses apprehend very accurately and time seems to elongate. When the brain has lots of information to process, it's tricked into believing that time is moving slowly. When we are going through familiar data, our brain needs not to undergo as much exertion as it would otherwise, hence time seems to pass at a quicker rate. This is the reason, why a life-threatening or a risky situation doesn't seem to come to an end!