When millions of people gathered to watch the series finale of Lost last night, they bid farewell not only to the characters they'd come to love, but also to the brilliant work of composer Michael Giacchino. (Well, I thought it was brilliant. Bob thought it was just awful). Each week for the past six years, Giacchino wrote and recorded the sometimes haunting, sometimes soaring music that accompanied Jack, Sawyer, Kate and the rest of the Lost cast on its utterly baffling journey.

It's incredibly difficult to come up with a half hour or so of original music on demand, week after week like that, which is probably why so many TV "composers" these days forgo melodies and fill their scores with long, ambient tones, usually played on a synthesizer. It's certainly faster and cheaper. Giacchino's music for Lost was unusual in that it was spare, but rooted in strong melodies and played with a live orchestra. It was actually one of the very few remaining TV programs to use real musicians. Imagine writing all the notes out each week on paper and giving it to an orchestra. They've got to learn all their parts, play it to the scenes to make it all time out perfectly and get it in on deadline. Every week. And for a while there, Giacchino was actually scoring two shows at once, Lost and Alias. Gurgle.

While a number of TV programs and films have worked well without a score at all (did you see No Country For Old Men?), music is usually a critical player in the way stories unfold. It tells us how we're supposed to feel, and Giacchino was a master at telling us how to feel while we watched Lost, even if we otherwise had no idea what was going on.

Producer J.J. Abrams actually came up with the little metallic, ghostly swoop sound that played at the beginning of every episode -- the 16-second main title that accompanied the 3-D "Lost" letters as they slowly spun toward the screen. While watching last night, I wistfully noted that it was the last time I'd hear it. Tuesday nights won't be the same without it. I'll also miss the blaring horn falls Giacchino tagged to the end of particularly suspenseful scenes, the beautiful arrangements and melodies that bloomed at all the right moments, and the way his music always made me feel both tearful and frantic.

Here's an interview with Giacchino talking about his work on Lost.