I'v been considering doing this doing this with my 512k with a MacGusto II upgrade for a while, the only reason i haven't done it so far was that the theoretical current draw of the SCSI2SD was surprising high, possibly up to 700ma during writes and i wasn't sure how much spare capacity is in the macs PSU (especially with the extra draw from my upgrade board, which adds scsi, 2mb more ram and a 68881 (when i get around to installing one))

I have been planning to measure the actual current draw for a while, but I haven't got around to it yet...