John Williams also scored the first three Harry Potter movies. His scores for the first two never really did much for me, but the score for The Prisoner of Azkaban was excellent. If you're into it, also check out Nicholas Hooper's score for The Half-Blood Prince, and Alexandre Desplat's for the last two.
Kudos to Keyblade for mentioning James Horner and Hans Zimmer, although I'd like to point out that, contrary to popular belief, Hans Zimmer did NOT score Pirates of the Caribbean: The Curse of the Black Pearl. That was his student, Klaus Badelt. Zimmers only scored the sequels.
If we're talking about soundtracks as in actual songs, not the musical scores, then I don't have a lot of interest in them, really. XXX (a tidy enough Vin Diesel movie) had a good one, I recall (Rammstein were on it, and the opening scene was actually filmed at a live Rammstein concert where they performed said song!). Personally, though, I prefer classical scores and symphonies in films, or instrumental electronic music if it's more suitable. Not keen on heavy use of bands/artists' material as I just don't feel it's anywhere near as effective. Only in specific kinds of films does sountracking work. But that's just my opinion.
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