MacFUSE and MacFusion

Macfusion is an open source Mac application that allows you to work with files on servers across the internet, as if they were sitting on your computer. Macfusion presents a Volume in Finder, letting you use your favorite Mac applications to work with them.

Requires MacFUSE.

MacFusion App

MacFUSE allows you to extend Mac OS X's native file handling capabilities via 3rd-party file systems.

Google Code