[Caduceus]

I must say I hadn't heard anything about Sky Captain until I saw the trailer in the theater a few months ago (along with Pitch Black's sequel). I was waiting after the first thirty seconds for someone to "snap out" of a dream sequence.

In regards to the theme musics, there are about ten or so pieces which you'll hear over and over again for various trailers, depending on the company releasing the picture. Over the Last few years, I've noticed a few recurrent ones:
Stargate - main theme
"Bishop's Countdown" from Aliens
The Patriot - theme

I'm sure you all know more too. But for the most part, it is a.) cheaper and b.) often the composer isn't involved at the point the trailer is released or he/she is working on the film and can't be troubled with a trailer.

Wildcard