Lets list "power rings" from books, comics, movies, etc

If Carmine Infantino had possessed a sense of humor, he’d have given us a few panels of Barry Allen, cursing under his breath, trying to cram his costume back into the ring at the end of a superhero gig.

It must have been a bitch to re-pack that thing.

Without his rings, Ringo Starr is only a middling drummer and a horrible singer. With his rings, Ringo Starr is…

…oh…wait…

Through one of those Internet coincidences I stumbled across this scholarly article today, and it seemed to fit this thread: “Magic Rings in Mythic Narratives” by Wendy Doniger
http://humanities.uchicago.edu/openhouse/keynote/doniger.pdf

The ring of Erreth-Akbe from the Earthsea books, although it was more like a torc than a ring, and had no magical powers; it was more a symbol of unity.

Oh, and from The Cat In The Hat Comes Back:

The water ran out
And then I saw THE RING!
A ring in the tub!
And, oh boy! What a thing!
A big long pink cat ring!
It looked like pink ink!
And I said, “Will this ever
Come off? I don’t think!”

Oggar God of Magic that turned evil and was banished from the earth by Shazam.

It would have been a good scene, but it doesn’t seem fair to lay its omission at Infantino’s feet. He was an artist, not a writer.