Not surprisingly, quite a few of those are in the public domain. I recognize the public domain titles.
I had a friend who had a collection of the 50 worst horror movies ever made. I'm still trying to scrub Eegah! out of my brain. It wasn't the horrible caveman that was frightening, but the lousy attempt at rock'n'roll singing by someone who can't sing or act around a poolside.
Kind of reminds me of the "Johnny" A-story parts of Alan Freed's Go, Johnny, Go! It's a "classic" only if you skip everything in between the classic oldies performance segments. The rest was cringe-inducing. It was clearly an attempt by Alan Freed to create a new teen idol out of a talentless individual by having famous legends talk about how great he is. Suffice to say, the kid didn't get anywhere.
And I'm saying this as someone who actually enjoys Elvis movies. These movies make his look fantastic (and I'm well aware of their faults). For rocksploitation flicks, those are among the best. You don't even want to see Beach Blanket Bingo or Go, Johnny, Go!
Also, Ed Wood has got nothing on Eegah! Ed Wood films are charming next to some of the things I've seen.
Haven't checked out Manos: Hands of Fate or Santa Claus Conquers the Martians, but I've heard they're supposed to be epically terrible.
Seen Turkish Star Wars before? That's easily the worst thing I've ever seen. It makes the Mighty Morphin' Power Rangers look high quality. You'll never look at trampolines and strapping rocks to your legs the same way again. Not to mention the stolen Star Wars space footage and the Raider's March as the theme. Oh, and while you're at it, check out Turkish E.T. and the Turkish Wizard of Oz. The Bollywood musical version of Superman, complete with Spidergirl, is also spectacularly bad.