Hello Brick (Ben Folds Five vs. Martin Solveig ft. Dragonette)

Ben Folds Five - Brick (instrumental)
Martin Solveig ft. Dragonette - Hello (acapella)

Light My Mother (The Doors vs. Danzig vs. Talking Heads)

The Doors - Light My Fire (instrumental)
Danzig - Mother (acapella)
Talking Heads - Psycho Killer (acapella)

Clocks with Butterfly Wings (Smashing Pumpkins vs. Coldplay/Royksopp)

Coldplay/Royksopp - Clocks (instrumental: Trembling Heart Remix)
Smashing Pumpkins - Bullet With Butterfly Wings (acapella)

Someday I Bleed U Into Pieces (Leona Lewis vs. Mariah Carey vs. Sum 41)

Sum 41 – Pieces (instrumental)
Leona Lewis – Bleeding Love (acapella)
Mariah Carey – Someday (pianopella)

Many thanks to Bobby G for this video:

Hungry 4 Teenagers (My Chemical Romance vs. Duran Duran vs. Gorillaz)

My Chemical Romance – Teenagers (instrumental)
Duran Duran – Hungry Like The Wolf (acapella)
Gorillaz – 5/4 (acapella)

Heart Of Confusion (Blondie vs. New Order)

New Order – Confusion (instrumental edit)
Blondie – Heart Of Glass (acapella)

Confusion Of The Heart (New Order vs. Blondie)

Blondie – Heart Of Glass (instrumental edit)
New Order – Confusion (acapella)
New Order – Temptation (sample)