The movie log, or as I'd like to spell it, the moovy log. Inspired by the ever so awesome Warren...
Big hand for Warren....rah rah, clapping hands, confetti and dancing girls to ya.
You mentioned Zardoz 
which, by the way, happens to be one of my all time favorite B movies.
I liked that movie so much.
They used crystals for their memory storage.
At that time, I had read they were developing crystals with blue lasers for computer storage.
I thought. "YES, FINALLY, a better medium than VHS tapes! I can free up an entire room now.". 
But they came up with DVDs instead. They looked just like CDs, but cost more.
DVDs confused to people, somehow.
I've seen people throw DVDs like Frisbees, put their finger prints all over them, and even use them as coasters.
Some people decorated their Christmas trees with them. They even hung them on their rear view mirrors.
But outside of their misleading appearance, DVDs are supposed to have a shelf life of 100 years.
Thats great, really great, but I don't keep mine on the shelf! I keep them in a coffee can. I actually watch them too.
They just don't last that long after all the sliding in and sliding out and spinning and screeching to a halt from 1,000 mph.
Another advance that I liked about Zardoz was the flying head thing.
Imagine, if cars flew and looked like your head. That would be great!
No more searching for your car in crowded parking lots.
You could just ask anyone if they knew where you parked. "yea, uh, that car over there looks just like you".