Some features of the Amiga that are peculiar even today:
1. The mouse is a hardware sprite and its movement stays responsive and smooth even under heavy load and even when the OS freezes
2. A screen can be divided into multiple resolutions, e.g. you can have a half a screen in high res and half in low res and with double the amount of simultaneous colors (or even HAM mode)
3. It can genlock natively, i.e. match its screen refresh rate with an inbound video signal, making it popular with broadcasting studios up to the late Nineties