I've seen people take SID chips and create little synth boxes to be controlled via MIDI. Seems a lot of people are willing to pay a nice amount to have such a thing.
So I'm wondering, how come nobody seems to be doing this with the Paula chip? Also has the Paula chip been cloned?
Unless you're one of those purists who can tell the value of the 8580 external caps in a blind test, then you could try strapping a Parallax Propeller chip to the serial port of your Amiga

Demonstration videos:
http://youtu.be/w_GTOvkdM5Qhttp://youtu.be/bawJFT3hSLwconsider that removing the video and SD parts from that demo, the audio generation only takes 1/8 of the processing power of the chip.
So putting aside some 2/8 for serial port and routing, up to 6 SID chips could be emulated with a single $8 chip.