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.
Sting of the Zygons
The TARDIS lands the Doctor and Martha in the Lake District in 1909, where a small village has been terrorised by a giant, scaly monster. The search is on for the elusive 'Beast of Westmorland', and explorers, naturalists and hunters from across the country are descending on the fells. King Edward VII himself is on his way to join the search, with a knighthood for whoever finds the Beast.