I have written a SANE backend to support the Fujitsu ScanSnap S300 and fi-60F.
These machines are pretty stupid in comparison to a 'normal' Fujitsu scanner,
with lots of features being provided by software on the host computer.
This code is included with SANE v1.0.19, though the version in SANE cvs
may include improvements.
If you have one of these scanners and need some feature or find a problem,
please contact the sane-devel mailing list, or me directly.