By default, SuSE 10.0 mounts USB disks with the 'sync' paramater. This is the safest way to do it, but reduces transfer speed by at least 10 times.

Here is a way to change the default behaviour:

• Create the directory /usr/share/hal/fdi/policy/95userpolicy
• Create the file nosync.fdi
• Put the following in that file:
  • <?xml version="1.0" encoding="UTF-8"?>
    <deviceinfo version="0.2">
    <device>
    <!-- disable sync for mount -->
    <match key="block.is_volume" bool="true">
    <match key="volume.fsusage" string="filesystem">
    <match key="@info.parent:storage.bus" string="usb">
    <merge key="volume.policy.mount_option.sync" type="bool">false</merge>
    </match>
    </match>
    </match>
    </device>
    </deviceinfo>
• Restart the HAL daemon with 'rchal restart'

Now when USB devices are mounted, they'll be mounted asynchronously.
You must be careful to properly unmount the disk before unplugging it!

Source: http://opensourcetutorials.blogspot.com/2007/03/my-experience-installing-and-using.html
Thanks!