So we are looking at the Agfa C-41 or ECP. The future of ECP is probably short due to the mass conversion of movie theaters to digital projection, which leaves us with E-6, Agfa C-41, or materials like the FujiClear film. A roll of the fujiclear would probably last photographers like us a very long time if we were to use it for contact prints of C-41 negatives. I wonder how well it would stand up to projection.
Wow this thread has gotten off-topic. We started out talking about future Kodachrome processing and now we're talking about how to get our slide fix if E-6 disappears (hey, I'm an optimist!). But that's okay this topic needs to be explored.