At the end of the Fringe episode "Transilience Thought Unifier Model-11", Walter finds and plays a CD to help himself "shift perspective, to see things differently."
The song that is played is "Only You" by the '80s band Yaz (née Yazoo).
iTunes: "Only You" by Yaz
Amazon: "Only You" by Yaz
Also, Fringe soundtrack composer Chris Tilton (@christilton) has posted a free MP3 of the soundtrack music from this episode, titled "Searching For Olivia Dunham" on his website ChrisTilton.com