Most Ironic or Humorous Item and/or Situation you've come across..

[persy]

On PC:5

You suddenly sense a taint in your vicinity. You sense a soul in agony. You sense a terrible loss.
Bastard nearly raped me. "I'm sorry tiny girl, we have to put Fluffybutt to sleep :-( ... ehm, later, when I'll be able to deal with him"

[Deathwind]

A quickling queen triggered an alarm trap only to get killed by a molch, my thoughts on seeing this? "dodge that"

[BenMathiesen]

Found in my current game, in Darkforge:

Anti-magical robes of power [0,+2]

Huh. Interesting, and not totally insane, but definitely ironic.

[persy]

Not the funniest moment but it made me smile.

Bandit picks up iron ring. Bandit equips iron ring. Iron ring suddenly glows in black light!
Bandit picks up gauntlets. Bandit equips gauntlets. Gauntlets suddenly glow in black light!
Bandit picks up uncursed greased boots. Bandit equips uncursed greased boots. Uncursed greased boots suddenly glow in black light!

Yes, dude, Puppy cave. It is here to break novice adventurers just like you and me.

[theseus12]

I found one of those

[Blasphemous]

Thread necromancer strikes again.
A few prereleases ago I found a funny item: sabre of swiftness of swiftness.
Apparently the game treated sabre of swiftness as a normal affixable item and give it one of the same name
This has since been fixed as far as I know.

Another situation: I walked through CoC pre-dwarftown. There comes a necromancer. He sees me and summons ghuls twice, steps on an alarm trap, gets attacked by his own ghuls, paralyzed and killed
Take that ye damned summoner!

Also had another summoner probably also step on an alarm trap. I arrived at the room full of spiders and a poisoned dark elven wizard corpse along the wall.

[LexyBoy]

Ha, I had something like that:

Yulgash, the Master Summoner, suddenly seems to panic!
A bright light flashes around Yulgash, the Master Summoner. Yulgash, the Master Summoner, staggers around aimlessly.
Yulgash, the Master Summoner, is hit by a stone block!
Yulgash, the Master Summoner, moves over a loose stone. Click! The air elemental is surrounded by the roaring flames (x10)!
The air elemental hits Yulgash, the Master Summoner. The air elemental hits Yulgash, the Master Summoner. The air elemental hits Yulgash, the Master Summoner. Yulgash, the Master Summoner is killed! The air elemental appears more powerful.

[Joe]

I had this pretty weird convo just now:
'The carrion crawler attacks the female goblin rockthrower. The carrion crawler misses the female goblin rockthrower. The female goblin rockthrower is killed! The carrion crawler suddenly looks more powerful. The carrion crawler suddenly collapses!'

[paivi]

A long time ago I found a royal vault and talked to the guard:

"Oh my, I'm so lonely and need some company."
You spend some time with Whatsisname the royal guardian who seems to enjoy your company. Whatsisname the royal guardian yells "Die scoundrel!" Whatsisname the royal guardian hits you.

Mixed messages, anyone?

[SirTheta]

A long time ago I found a royal vault and talked to the guard:

"Oh my, I'm so lonely and need some company."
You spend some time with Whatsisname the royal guardian who seems to enjoy your company. Whatsisname the royal guardian yells "Die scoundrel!" Whatsisname the royal guardian hits you.

Mixed messages, anyone?

I like to imagine this is what happened here: https://www.youtube.com/watch?v=O1PK4qYzNkI