I thought this might be useful to some portable app developers. The program is called UPX Mass Compress (which uses... UPX, who would have guessed?), and it's a simple program that quicky compresses a bunch of dll/exe files. This program saved me lots of time for the two portable applications I maintain, especially with all the dll files in Portable Scribus.
Here's the download and information page:
Hopefully this is useful to someone, as I took the effort to make it public. I probably lost the time I saved from using this program, to make it ready for a public release.