Such as? I can only think of the Rings from LotR and the thing they were inspired by, the ring from Der Ring des Nibelungen.
What are the other mythological and legendary precedents? Please enlighten me. How do they compare to other mythological and legendary items? Are ANY mythological or legendary items not "objects of great power"?
As I mentioned in another thread (
http://www.enworld.org/showthread.php?t=217274&page=4&pp=30 see post #101), semi-trivial rings exist in all kinds of forms. Plato's Republic mentions a ring that makes a man invisible- that's it. Two historical rings have the equivalent of "Healing" spells inscribed in them.
Cloaks of invisibility and pouches that are always full of just enough money to pay for your purchases appear in Grimm's Faerie tales- powerful in their context because the context is extremely magic poor relative to a typical RPG.
Others from European legend include Sleeping Beauty's poison apple that put her into suspended animation and Rumplestiltskin's magic spinning wheel, Jack's beans, and the singing harp he found in the castle in the clouds...
From Sir Gawain & the Green Knight comes a sash or ribbon that protects the wearer from 1 blow (only) from the Green Knight's axe (only).
Crystal balls, scrying bowls, Seven League Boots, Magic Mirrors on the wall - all from legend.
Talismans of Dionysus supposedly warded off insobriety, while certain fetish objects warded off impotence.
According to anthropologists, many charms and pieces of art made by Neandertals & Cro Magnons were examples of sympathetic magic designed to improve (but not guarantee!) the odds of a successful hunt...and to ward off retibution by animal spirits afterwards.
From Dickens' The Christmas Carol, The Ghost of Christmas Future's cornucopia could make people happy if he shook it over people.
Peter Pan's Pixie Dust.
How about Love potions?
That's off the top of my head- if I scour my encyclopedias of mythology and look at African, Asian, or Native American legend, I'll find more.