The 'Secure Digital' or 'SD Card' mass storage standard, while fundamentally a proprietary standard, and certainly nowhere near as open as say CompactFlash, has nonetheless become common in DIY and open-source hardware, providing flash memory storage (as of 2010) in the small numbers of gigabytes for perhaps a few dollars per gigabyte. As of 0.9.17, the SFB core software has had support for performing raw disk operations -- no file system, just reading and writing blocks -- on SD cards.