"Hallelujah" is a song written by Canadian singer-songwriter Leonard Cohen, originally released on his album Various Positions (1984).
Many cover versions have been performed by many and various singers, both in recordings and in concert, with over 300 versions known.

http://www.youtube.com/watch?v=eb2VV0TkQdc

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http://www.youtube.com/watch?v=eb2VV0TkQdc