Macosx can read fat drives, so i would imagine a usb card reader of some sort will let you access it on the mac. Then one of them pcmcia convertors to plug into the a1200, i was using one the other day. Works fine, cfd and fat95 were all that was needed.
i guess the network way would be more fiddly, at a push you could run ftp server on one and ftp to it from the other.