Most compelling vocal you discovered in a movie?

I love music and find myself drawn to all sorts, most kinds of jazz, opera (except Wagner, which I have seen performed), rock, pop, world, etc. The radio, TV, concerts are obvious places to discover new tunes. How about the movies? Is there a song so wrenchingly beautiful that you discovered while watching a movie that you sat around to see the credits and then rushed off to buy it? For me the most recent tune was "When I Dream" by Carol Kidd in the highly recommended South-North Korea espionage drama "Shiri." The song is wonderful and fits the movie just so. If you haven't seen this, I urge you to find it somewhere. It was the highest grossing film in Korean history and while it is explosive, the character development and underpinnings of the motivations provide some nice food for thought.
In "Grace Of My Heart," Illeana Douglas lipsynchs a Burt Bacharach song about a failed relationship, "God Give Me Strength," that just broke my heart. I didn't buy the movie soundtrack (I own the laserdisc), but the song is on the Bacharach/Elvis Costello CD, Painted By Memory, and it even works with Costello 'singing' it.
I've got two: for a song that I was previously unfamiliar with, "Harlem Blues" from the Spike Lee movie. For a new performance of a standard that absolutely blows you away, "How Long Has This Been Going On", from 'Round Midnight.
Two schmaltz nominations: "It Had to Be You" by Harry Connick Jr from When Harry Met Sally, and "The Sound of Music" by Julie Andrews from the movie. A sentimental favorite: "The Look of Love" by Dusty Springfield from Casino Royale.
Here is one, but I do not know the name of the cut.
In Fifth Element, the 'blue' lady sing an absolutely stunningly beautiful piece. This is FAR and away my most favourite, but I do love classical. If ANYONE knows this piece, and who actually does this, or the CD name, please let me know. Do you recall the scene?

Once I was watching a movie "Professional" with Jean Reno and Gary Oldman.
I wasn't impressed in general from this movie but the only thing I loved was the final song of Sting during the credits playback. I believe that everyone knows that song and I knew it too some time before this movie, but without full understanding of lyrics since English isn't my first language.
That day this song broke me through and I've memorised almost all lyrics from that listening!
Another movie that worth listening songs IMO is Natural Born Killers where Leonard Cohen has a bunch of musical credits.
The aria from La Wally from Diva. And, the choir piece from Empire of the Sun.
That bit in Sam Peckinpah's Pat Garret And Billy The Kid where Bob Dylan get's on his bike and starts singing Raindrops Keep Falling On My Head and then Coburn shoots him.
That was fun......
Porschecab I agree. "Lucia Di Lammermoor" performed by Inva Mulla Tchako with the London Symphony Orchestra. The Fifth Element is also by the way a very well done dvd.
Natural Born--- is where I got hooked on Cohen. He has music in more movies also. I ran out and bought an Inya album after hearing it in a movie I can't remember the title of. There is so much good music in movies.
I like "Life in Mono" performed by Mono for the movie "Great Expectations". I bought "Great Expectations the Album" and found that I not only enjoyed this vocal, but all of tracks 1-9 and 12. I'll also put is a second vote for the 'blue' lady (here actual character name in the movie is Diva Plavalaguna) vocal from "The Fifth Element".
Have to admit that the one that really, but really grabbed me was the Peter Gabriel song, Blood of Eden, from Wim Wenders' movie, Until the End of the World. About half way through the movie, after a chase all around the world in half-comical, dark futures, cyber punk-ish vein, the two protagonists have escaped their pursuers and are flying into the Australian outback in an single engine plane. It's really noisy, they're happy and shouting over the engine, when there is a flash (which we know is a nuclear satellite exploding in orbit and covering things with an EMP pulse killing all electronics -- sounds improbable, but it's all in keeping with the world of the movie), the engine dies and there is suddenly nothing but near silence, the wind, and the tentative whisper, "it's the end of the world." So, into the silence as the plane drifts down to earth, Peter Gabriel kicks in with Blood of Eden.... For my money, this moment has to be one of the most perfect moments on film, and I was instantly obsessed with the tune.

Now, it's NOT the version on Gabriel's album, which is far more elaborately instrumented -- the one I'm after is much more bare and plaintiff. And it's not on the soundtrack at all (to my dismay), although the soundtrack is great in its own right. And, to this day, I haven't been able to find a copy of the version used in the film. Anyone have any pointers...?

Have to admit that I was exceptionally taken with the track used at the end of Hannibal, as well. After having endured (and I do mean endured) that movie in the theater, rolling the credits to such an ethereally haunting choral arrangement fairly well took my breath away. Bought the soundtrack on the way home (which is otherwise, in nearly every way, unremarkeable -- alas).