The main thing I always stress about these intros and the music (at least with the Amiga) was that this was still all before we used CD-based consoles and such. The music you hear, is being heard right from the sound chips of the machine itself, not some pre-recorded CD music. Heck, I can outdo many of the CD-based musical intros with my studio, so they impress me less. But we're talking music that generally takes 100KB or less and still rocks.
The Amiga often used samples in its tracks, but then you had realtime sample manipulation and mixing done right with the tracker and the Paula soundchip. This allows full length, great quality music, to be produced with very little memory needed. I actually programmed quite a few tunes between the C64s SID chip, and the Amiga's Paula. The Ami, I had a lot of fun with, because you find inventive ways to make stereo 4 hardware channels sound like a whole lot more. I'm thinking of uploading a bunch of my "Mystik Tank" soundtrack songs (all Amiga), for people to sample. Every song is around 80K or less, since I wanted only a small section of chip memory to be used for music (all of it was meant to be used in a videogame, with some songs providing background music to computer animation w/sound). The game was to run on the AGA machines, even with just 2MB Chip Ram factory defaults. It ended up being one of the many unfinished projects late in Amiga's popular lifecycle, due to a loss of programmers needed to finish it.
