Did you ever think about having a Bluetooth connection to your CPC, e.g. to transfer your data or DSK images directly from or to it? Of course it is possible and it is very simple to realise that, plus: you can use all the tools, which already work with the CPC Booster+. I already use this setup for nearly a year and found the time time to document it. You can find the documentation in the articles section of this page.
DaDMaN, a spanish CPC user, created a prototype to connect FTDI’s Vinculum VDRIVE board to the CPC. With the Vinculum it is possible to connect USB storage devices to microcontrollers. He also published two videos on Youtube which show the prototype interface in action:
I already own a VMUSIC 1 (no longer available for private persons) module and have connected this board to the CPC with the CPC Booster+. I used a simple MAX323 level shifter to connect it. You can do this with every RS232 interface of the CPC and use the terminal program to send commands to the board. Here is an image of mine: