For new users it would be cool if they could select portable apps on a web page and when they made their choice, they could download a custom a zip file with the selected apps bundled in it. Since the portable apps installers simply copy the contents to the flash drive, this can easily be done on the server side. For those that don't understand this idea very clear: Mowes has something similar (see http://www.chsoftware.net/en/mowes/mowesmixer/mowesmixer.htm?step=2).
The installers don't simply copy their contents. There's a lot of logic for handling languages, upgrades, automated downloads of online bits that can't legally be bundled and lots more. Over 2,000 lines of code.
Plus, our downloads are via SourceForge which doesn't support this. If we took the download bandwidth in-house, it'd be $20,000 a month and we'd have to charge for downloads.
We are working on something similar for release in the near future, though.
Sometimes, the impossible can become possible, if you're awesome!