This time, the list is mighty long. So, let me spare the extra descriptions already elucidated in the respective reviews and present the list, directly!
Know Your Enemy, East Jesus Nowhere, Last Night on Earth & Restless Heart Syndrome: 21st Century Breakdown (Green Day)
Kooda Varuviya: Valmiki (Tamil OST), Ilayaraja
Oy & Sehri: Oy (Telugu OST), Yuvan Shankar Raja
Danchave Remix: Ride (Telugu OST), Hemachandra
Meghamaa: Prayanam (Telugu OST), Mahesh Shankar
Kannil Dhaagam: Achamundu Achamundu (Tamil OST), Karthik Raja
Adhikaalai Pookkal: Moscowin Kaveri (Tamil OST), S S Dhaman
Saarale Saarale: Vedigundu Murugesan (Tamil OST), Dheena
Om Shanti Om: Mutthirai (Tamil OST), Yuvan Shankar Raja
Love etc.: Pet Shop Boys
Alele Savaari & Kannambaadi: Thaakath (Kannada OST), Gurukiran
Mayilaattam Oyilaattam: Malayan (Tamil OST), Dheena
Kannil Theriyum Vaanam & Kadhaigal Pesum: Angaadi Theru (Tamil OST), G V Prakash Kumar
Muthamma & Enna Senjaalum: Azhagarmalai (Tamil OST), Ilayaraja
Nisapaa: Mukhaputa (Kannada OST), Hamsalekha
Paadhi Kaadhal & Vellaikaari: Modhi Vilayaadu (Tamil OST), Hariharan & Leslie Lewis
Gore gore: Kick (Telugu OST), S S Dhaman
Vaa Chellam: Thoranai (Tamil OST), Manisharma
Nila nee vaanam Azhagu Mugam: Pokkisham (Tamil OST), Sabesh Murali
Shatki Sahida Ganapatim: Vismaya – An Indo Celtic Musical Journey (Kanniks Kannikeswaran)
Swapnangal Kannezhuithiya: Bhagyadevatha (Malayalam OST), Ilayaraja
Inteha Aaj Bhi: Inteha (Ghazal), Jagjit Singh
Durga & Drop if Earth: Advaita (Indipop), Advaita
Oru Devadhai: Vaamanan (Tamil OST), Yuvan Shankar Raja
Ekanay: Alone, Loved & Lost (Malayalam Pop), Rashee
Yeh Kaali Kaali: Housefull (Telugu OST), Anoop Rubens