[lug] JBOD File Browser?

[Lori Reed]

Has anyone run across a file browser that could treat two or more drives 
(mount points, actually) as a single entity similar to JBOD but 
guaranteeing that no single file will ever span drives?

Or how about software that would allow two or more external drives to be 
mounted with a single mount point in a JBOD fashion?

Either nothing like that currently exists, or my Google-Fu has failed 
completely.

I have need of and am considering writing such a file browser, but I'm 
not sure I'm all that ambitious at the moment.

Lori