FWIW, I think the USB stick idea is a great one, and for more stuff than Slackware.
Already, some artists have been distributing their (music) singles and/or albums on USB stick (Bare Naked Ladies comes to mind IIRC). Among other things, it gives you something that's literally more useful
(a USB stick vs. a plastic disc) and doesn't have to be tossed in the trash when it gets a little scratch on it. Plus, someday maybe there will be (if there isn't already) kiosks, so to speak, where you can swipe your futuristic payment/identity card, plug in your Slackware USB stick, and have it refilled with a new batch of great Open Source Software