Just dug this up on the mchip site, thought it might be worth mentioning to the list. http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en024394 Title: USB Mass Storage Device Using a PIC MCU Name: AN1003 Date: 8/30/05 Author: Gurinder Singh Description: This application note describes the design and implementation of a USB Mass Storage Device (MSD) using a Secure Digital card Keywords: Mass Storage, USB, Secure Digital, Flash Media, Multimedia, PIC18F4550 -Denny -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist