Over on Atariage, I found information about
The Stelladaptor. This is a small USB device that gives you an Atari 2600 joystick port, to which you can connect joysticks and paddles. So what, I hear you ask? Well, the Atari 2600 had the same joystick ports as Amigas! Might be a nice thing to get AmigaOS/MorphOS drivers for.
I wonder if its compatible enough to work with CD32 pads?