Change media upload files to upload to different path sometimes

Hi there

I’d like to edit the media upload files in WordPress 2.9.1 to accept a parameter (on media-upload.php) so that files uploaded using the parameter are uploaded to a hard-coded, different directory other than the default just for that instance when the parameter is used…

For example:

Say http://blahblah.com/wp-admin/media-upload.php?type=image uploads to http://blahblah.com/images

How do I change the system so that:

http://blahblah.com/wp-admin/media-upload.php?type=image&differentpath=yes

will upload to http://blahblah.com/different/path/images

Thanks!