Thanks for the responses. Must admit I'd never heard of a WiFi SD card before. That would be great for just putting files on the SD card, but I was hoping to be able to control and monitor as well. Currently I have about 75ft of Ethernet cable running from the computer to the printer, connected at either end to USB repeaters so I can connect Computer USB to Printer USB and get full control / functionality from S3D at the computer. I was hoping to be able to replace the cable with a WiFi link. I have some spare arduino boards and WiFi modules hiding around the place... maybe time to experiment.