0xdff058
I too have fond memories of the Amiga, I loved how open the platform was (especially for the time). I spent many an hour writing code in 68000 and C and abusing the hardware, timing my code in raster lines, and my first Internet usage, with KA9Q then AmiTCP.
Today Linux is my weapon of choice, but it was the Amiga that set me on my way!
Is it sad that I remembered my favourite hardware register, 0xdff058, almost quarter of a century later without having to google?