I thought, you really don't hear a lot of those any more. And it's a bit of a shame, really. While the songs themselves aren't all winners, their presence helps complete the package; the film as product. What prompts a producer to pursue a special-purpose song? It's all part of a film's marketing--radio play certainly helps keep the film front-of-mind. And casting a singer in a major role generally ensures a unique musical composition. Conversely, an actor might seek to expand into music by lending their voice to the film's soundtrack.
Some movie themes are awesome. Others, not so much.
Original Sin - The Shadow
Taylor Dane lends her soulful voice to The Shadow's incongruous theme song. I could make an argument about how the lyrics fit the film, but why bother. It's not a very good song, but I still kind of like it. I feel the same way about the movie.
Batdance - Batman
Danny Elfman wrote a brilliant theme for Tim Burton's Batman, but Prince went another way with his contribution to the movie's soundtrack. There's no questioning Prince's talent, but the song and video skew more campy than dark, harking back to an earlier Batman.
She's a Looker - Looker
Michael Crichton's dark exploration of media and advertising has an 80s-tastic theme song that completely fails to capture the movie's mood and atmosphere
Shocker Theme - Shocker
There is no official video, as far as I know, which just goes to show you how well Shocker was expected to perform.
Cancion Del Mariachi - Desperado
I don't speak a word of Spanish, but that doesn't stop me from absolutely loving everything about this song, starting with Antonio Banderas. The song is performed over the opening credits and segues seemlessly into the start of the film.
Hold Me, Thrill Me, Kiss Me, Kill Me - Batman Forever
A rare instance in which the song and video are far, far superior than the film itself. I still have no idea what this song has to do with the movie, but it's freaking U2 so who cares.
Beast Loose in Paradise - Dark Floors
This might be cheating a bit, because Dark Floors features glam metal band Lordi as the monsters who torment the film's characters. But I like Lordi, and while this song isn't their best, it was written for the movie.
Princes of the Universe - Highlander
Queen is all over the Highlander soundtrack. It could be argued that Who Wants to Live Forever is a better song, but it wasn't the official movie theme song.
Flesh and Bone - Suck
Cheating again! Suck is a rock 'n roll vampire movie so it stands to reason the soundtrack would be chock full of custom built songs. However, Flesh and Bone is not performed by the movie's heroes. It's sung by the badguy.
We Don't Need Another Hero - Mad Max: Beyond Thunderdome
Auntie sings about a better life beyond the Thunderdome. Weirdly, I can't find an official video for the song, but it was a huge hit for Tina Turner.
Never Ending Story - The Never Ending Story
Holy shit, Limahl's a dude.