A song originally by the band Tears For Fears from their first album "The Hurting" released in 1983.
The song gave Tears For Fears a number three hit in 1982.
Some time later in 2001, Gary Jules released his "Trading Snakeoil for Wolftickets" album. In it, his cover of Tears For Fears' Mad World which was used in the cult flick Donnie Darko's soundtrack released the same year.
It's amazing how different two covers of the same song can be. The original being so "80s" and Gary Jules' being quite "creepy" and dark.
Again, some more time later in December of 2003, after being quite an outsider track for the number one spot, Gary Jules' cover of Mad World topped the charts in the UK for three weeks over the Christmas and New Year period.