The most practical application of something like this would in shops where you have lots of web developers who are not versed it the standard file transfer methods. This could save you lots headaches in training X number of developers the ins/outs of FTP or SCP, plus the security risks that might cause.

I would be tempted to write something like this from this approach:
1) have the bulk of this program be on the in-house "devel" web server
2) write it as a wrapper for scp (which can be made to work through firewalls pretty easily)

This would keep the security of scp without adding the possiblity of creating new security holes
At this point you could write the app to be as grandiose as you wanted, integrity checks for the file, bulk uploads of major sections, etc...

/\/\averick

(be kind this is my first post to perl monks...)