1) Not at the moment. If you wanted to create a commercial version for our
    machine Sun would ask you for a $50k license fee.

 2) Have a chat with HiSoft. They do one...

 3) Sorted. I haven't used yours, just our standard one...

 4) You'll only need a three way cable.

 5) For a three way one you can connect pin 2 to pin 3, pin 3 to pin 2 and pin
    7 to pin 7. A good, cheap way to get a very long cable (long enough to go
    between two houses) is to buy a long telephone extension cable reel (you
    can get them in Argos) and then just to buy two serial ports from Maplin.

 6) You certainly can. Contact Gasteiner or Golden Image. The only problem is
    that those cards are designed for the A2000. They will work on the 4000,
    but they are only 16-bit ram and thus not even as fast as motherboard
    memory. However, they are pretty cheap...