@ Gwion
I suggest you pop over to OldSkool UK (
www.oldskooluk.org) and look up Zetr0's Project A600+ (if you Google that you should find it).
It shows what can be squeezed into the A600 case and expand the little Miggy without breaking the bank. PCMCIA SRAM cards are expensive these days, but the PCMCIA to CF adapter is a must-have, get this little beauty and a card reader for the PC and the Amiga ADF files are yours to explore, add a 3.1 ROM and you can run OS3.1 on the A600 and OS3.5 if you fit a laptop CD or DVD drive.
Cheers
WTF