Every Level 1 character's favorite artifact!
Hello Natalya! Welcome to Nethack. You are a chaotic female elven ranger.
Name an individual object? [ynq] (q) y
What do you want to name? [a-f or ?*] a
What do you want to name this elven dagger? Sting
a - the +1 Sting (weapon in hand)
Sting is somewhat useless as an artifact, but definitely is better than nothing for beginners. Its most important ability is that it detects orcs; When wielding Sting, you know where orcs are moving at the time.
Sting is an elven dagger, and has cost of 800 gp. It's a chaotic artifact. It has +d5 to-hit and x2 damage against orcs, orc mummies and orc zombies. It has the warning instrinct, specifically of orcs. It also cuts the webs. It can be present in bones files and may be generated randomly. Orcs (including player characters) cannot wield Sting; it will burn them.
It is one of the few artifacts that can be got by #naming a normal item, and can also be got from #offers and wished for. Of course, this is one of the most useless things your god can give to you and only a complete and utter newbie can wish for it! You probably should damn well find all #nameable artifacts before you start #offering stuff, and if you get a wish, get Mojo or Stormy or something instead of this...
But it is nice because some classes (like my elven ranger in the example) start with elven daggers - it's nice to threaten the Monsters right from turn one with your very own artifact weapon!
(Sources: Kevin Hugo's and Dylan O'Donnell's spoiler files.)