The winner demo of The Gathering 93 Amiga 500 demo compo, by Kefrens. Spans two disks, and dozens of parts.
A true classic, with a high-pulse beat and synched design. The effects are exciting and trancy but now a bit dated. But you can still see that this is good stuff. Faked texturemapping still has its qualities.
Highly recommended, and seeing it will give you a glimpse of the amiga 500 demo scene at its peak

Hidden part number two: Boot disk 2, push the left and right mousebutton and the joystick firebutton simultaneous for an intro with music and effects.
Hidden part number one, anyone?

Some says its a true contender vs. "Second Reality" by "Future Crew"