Sting (Middle-earth)
Sting has the magical ability to detect orcs or goblins nearby, glowing blue in their presence, as it did when the Fellowship encountered orcs in the mines of Moria. Tolkien establishes this as a common property of First Age Elf blades, particularly those forged in Gondolin. Sting is also exceptionally sharp. Bilbo manages to thrust it without effort deep into a wooden beam at Rivendell. Frodo also wounds a troll in Moria, after Boromir notches his own sword with his attempt. Sam uses Sting to cut through the giant spider Shelob's strong webs with ease, and also wound the spider, driving it away from the paralyzed Frodo.
Fafnir
It is clear that much of Tolkien's work was inspired by Northern Myth. Many parallels can be drawn between Fafnir and Smaug, from "The Hobbit", as well as between Fafnir and Glaurung, the first dragon in Middle Earth, who is slain by Turin. The exchange between Bilbo and Smaug nearly mirrors Fafnir's and Sigurd's. The main difference being that Sigurd's conversation occurs after the death blow has been struck. This is most likely due to dramatic effect, as Bilbo has much more at stake when speaking with Smaug. The other dragon Glaurung has many similarities as well. In Tolkien's "The Book of Lost Tales", Glaurung is described as a flightless dragon that hoards gold, breathes poison, and has "Great cunning and wisdom". In Tolkien's book "The Children of Húrin", he is slain by Turin from below much like Fafnir. Turin and Glaurung also have an exchange after the mortal blow is dealt.