In the middle of ripping box-sets to our media server I had a little bout of nostalgia for the 'ole days. After a little messing about I got the latest version of Hatari running which still seems to be making releases. It does a very creditable job in handling Atari ST emulation including some of the demo effects which abused the shifter hardware. After a couple of false starts I finally got this up on YouTube:
It may not seem like much but you have to remember how much less powerful hardware was back then. It took an appreciable amount of a frame (at 50FPS that's 20ms) to just clear the screen. One thing I do remember is it made use of the 68k's movep instruction to do the 8 pixel wide morphing of the main logo. This made it fairly efficient despite the ST's 16 pixel wide, 4 bit-planes.