If you can manage to hum a few notes of a song you heard briefly into the telephone, this new student-based software will find your song for you.

Read about it in an article Joanna Corman for the LA Times:
College seniors fine-tune music search
Computer program designed in a for-credit course identifies songs by just a few notes.

This is how it works. You sing a few notes of a song into a microphone or the phone. The software converts the notes into a wave and then extracts the notes and their duration. A database has snippets of 500 melodies. The computer calculates the pitch and rhythm and then compares that data to songs already stored. The top 10 closest matches pop up. Only the “main theme” or melody of the song is stored because it is most recognizable, said Yelinek, the team leader and a computer science major.
The program accounts for various versions of the song, including those in different keys. Songs can be hummed, whistled, sung or played.

“You might harmonize it differently. You might have a club mix, but still it’s recognized,” said Huang, a computer science and music major.

The students’ project was part of a program that dates back to the early 1960s. It allows companies, government agencies and nonprofits to approach Harvey Mudd students with problems to solve. Companies give the students, mostly seniors, upward of $30,000 for their research. There have been about 1,000 clinics since the program’s inception and it covers computer science, engineering, physics and math.
The software, which Seet said should be available later this year, has several uses, including copyright protection. It can be used for karaoke, which Seet called a “huge market.”