Memphis is a replacement RAM-based filing system (with lots of knobs on!)
that uses the System Sprite area rather than the RAM disc area. In
particular it;

* Provides a dynamically resizeable ramdisc by using the system sprite area
  for storage. (In sprites so it's compatible with other users)

* Up to 30 character file names (beware old filer 10-char bug).

* 2.00 has a new storage scheme, that can use a slave filing system
  instead of the Sprite area.
  Each file is compressed by the Acorn "Squash" module in ROM.

* Filer is now vastly improved, including a quit menu a la RO3 ramfsfiler,
  and files can be dropped into it directly (from an application saveas box
  or from filer)

* Automatically grows and shrinks sprite area.

* Comes with full source code, including a previously unreleased C library
  called 'FSLib' that provides facilities to do D.I.Y FileSwitch filing
  systems (like MemFS). Coming soon! FSLib that supports RISCOS 3 Image
  filing systems!