Funniest achievements you have unlocked in Steam?

Almost all the achievements in Dungeons of Dredmor.

Turd Burglar in Duke Nukem Forever.

From everything I've played, Magicka has the most entertaining achievements. But then, the entire games is meant to be, and mostly succeeds in being, entertaining.

Dirt 2: Two Cups One Girl :D

Those two were fun
The first one is when you are escaping and fall into the obvious trap of gladOs :D
The second one is actually when you enter in the scan, but the fun part is when you recalibrate the turret controler to make pass all the defective turrets, there are plenty of funny quotes ^ ^

Penny Arcade Adventures Ep. 2

Torchlight 2 has tiered achievements for leveling skills. The first tier for the fishing skill is "Apprentice Baiter". Unfortunately they named the top tier Master ANGLER instead of the hilariously obvious joke I thought I saw coming.

Head Shred Redemption - CS:GO :P

"Two Cups One Girl" in DiRT 2. I laughed hard when I got it. I had to win two team events with the same female companion. I think it pretty much explains itself regarding why it's funny.

Torchlight 1
The Horse Whisperer
Achieved enlightenment by speaking with the horse 100 times

You shall not PASS! from Sanctum. Il add more if I remember

Akai Katana Shin — “UUUURRRRGGGH”. Got it for dying immediately after starting the game :P

http://i.imgur.com/tyZCDxQ.png

RPG Much in Magicka. Not the funniest name there, but they way you get it is awesome.

Ladder Goat from Call of Juarez: The Cartel

Find Ladder Goat movie on the Fort level.

Reference to this

This one from LEGO Lord of the Rings

http://www.xbox360achievements.org/game/lego-lord-of-the-rings/achievement/73768-One-does-not-simply---.html

This one.

This made me laugh when I got it (stupid GFWL rather than Steam achivements) - http://www.xbox360achievements.org/game/f1-2011/achievement/57435-They- Especially considering how difficult the race was and how pumped I was.

Expert Excrement Expeditor -> Fallout 2
Took a banger in the mouth ---> postal

The one in Saints Row 3 where you had to assault 50 people with the dildo bat. Or was that punch/kick 50 people in the balls? It was one of those two.

Insulted other player while defusing a bomb -> CS:GO not really...

There is also a nice achievement for Homefront called Tea Party (Successfully examined 5 enemy corpses). You need tea bag 5 recently killed enemy players 5 times :D

Magicka had a good one called Steam or something like that.