FM
That Thing You Do! (Cheesy but bouncy)
Rancho Deluxe (For the Jimmy Buffett completist)
Danny Elfman sounds a lot like the lead singer from Oingo Boingo. 
Goodfellas and Boogie Nights are usually listed in these threads, and I’ll do so now. Of Scorsese’s movies, *Goodfellas * makes the most of its period music, I think – Casino, while not a bad film, had a great soundtrack as well.
P.T. Anderson had a huge palette of late-70s and early 80s songs from which to place in Boogie Nights soundtrack – he hit a grand slam, I think. None of the period’s songs were written with the movie’s scenes in mind, of course, but watching the movie, you’d think they were.
Dances With Wolves has been mentioned in a recent unrelated thread on this board – it’s extremely evocative (composed by the forementioned John Barry, IIRC) and is one of my favorite orchestral soundtracks.
Larry Borgia – that Casino Royale (spoilered) reference is a great one.
Peters Friends
“Southern Comfort” was a average movie but had a kick ass soundtrack by Ry Cooder. I just wish that it was availble on CD.
Amen to that!
For movies, I am VERY partial to A CLOCKWORK ORANGE.
Believe it or not, **The Hindenburg ** (1975) had a pretty good music score by David Shire, and a witty, satirical song, “There’s a Lot to be Said for the Furher” (lyrics by Ed Kleban).
I always liked the sound track to The Big Lebowski, fitting and not bad to listen to on its own either.
The music Air did for The Virgin Suicides wasn’t bad either, some of it better than what they’ve put in more recent albums.
And as an aside, it was great to hear a strain of music from the original Star Trek replayed in The Wrath of Khan. That sort of brass lament, when Khan appeared to Kirk, sent a bit of a shiver down my spine (seeing as how I’m a fan!) and was the perfect way to let us know Khan was back and was a little peeved being left on Ceti Alpha V.
And Kill Bill, both volumes.
The Blues Brothers
One movie that had a soundtrack that I just had to hear again and again was Ghost Dog: The Way of the Samurai (1999) with music by RZA and others listed here.
The main theme is one of those things that captures the spirit of the movie and has such a haunting quality. Hard to hum, too! 
Hahaha, I started because I was going to mention this…
I would also like to second The Commitments and The Blues Brothers soundtracks.
My contribution is The Lost Boys sountrack. Very good overall but I think the “People are Strange” cover is really good.
Rob
The soundtracks to Romeo and Juliet, The Crow, and Singles are among the best of the 90s.
Instrumentally, I always loved the soundtracks to Dances With Wolves and Braveheart.
Snatch is a great “party tunes” disc. It’s eclectic and you can dance to it.
No votes for the Graduate yet? Guess I’ll be the first.
Amen to Twin Peaks. I finally started watching my DVD set last week and was just blown away. I don’t know of any show that used music the way TP did.
For television, Supernatural has an excellent classic rock soundtrack. And Christophe Beck contributed greatly to Buffy, the Vampire Slayer’s atmosphere and story with his original instrumentals during his fifty-nine episode involvement; in fact, I wish they’d release a CD or two with just his music.
I’m suprised none of the Wes Anderson movies have been mentioned. I think he and Mark Mothersbaugh do a great job. I also loved Shaun of the Dead’s soundtrack.
Three soundtracks from movies really appeal to me:
Blade Runner soundtrack by Vangelis
The Shawshank Redemption soundtrack by Thomas Newman
Passion (Soundtrack to “The Last Temptation of Christ”) by Peter Gabriel
Some of my choices have already been mentioned (Pulp Fiction, Kill Bill, Goodfellas, Scrubs, Garden State), but I’d like to nominate a few more:
Neil Young’s haunting instrumental soundtrack for Jim Jarmusch’s bizarre western Dead Man (and I usually don’t like Neil Young at all!)
Grosse Pointe Blank (great selection of mostly '80s alternative; I believe John Cusack is a fan of most of this stuff and had a hand in choosing the selections.)
Grey’s Anatomy (very similar to Scrubs in that they choose an excellent array of modern, off-the-beaten path songs from hip artists that complement the action perfectly.)
Transformers: The Movie (the 1986 animated version, not the one coming this summer – it’s a great collection of synth-laden hard rock and not-too-heavy hair metal guaranteed to get you PSYCHED UP! I can only imagine the amount of cocaine consumed by the no-name bands on the soundtrack. Oh yeah, and Weird Al appears with a subtle tribute to Devo.)
American Grafitti
FM
Blues Brothers
have been named previously, so I’ll express my agreement for those and nominate
Tin Cup
Saturday Night Fever
American Hot Wax
When Harry Met Sally
Fabulous Baker Brothers
Though the movie is not good, “Daddy Day Care” has quite a decent soundtrack.