Why does any language have a word for this? Are German people meeting their exact doubles so often that they have to have a word for it?
bastardos
(I’m not sure if that is a real word or not)
I like Spanish carajo. It’s an vulgar interjection of annoyance, but it’s not just the meaning I that like – it’s how it feels when I say it. ¡Ay, carajo! just seems more annoyed than Aw, shit!
There are bunch of others I’ve noticed that I like, but of course I can’t think of any now.
In Yiddish, I like fakakte, meshugge, shvitz, and verklempt, among others.
German, I love Weltschmerz and Fremdsprachenkorrespondentin. The last one because it’s an excellent example of German shoving a compound noun into one word. It means a female correspondent with foreign language skills. There are others in German I’ve noticed, but my German has fossilized and been forgotten.
Yeah, not like those pixies, centaurs, and leprechauns I see every day. 
Thanks. Now, I know I need duyen to help me find the woman full of duende I’m hiraething for to appease my haiko.
Caio!
In Italian “500” = Cinquecento - pronounced “chink-way-chen-to”
it’s just one of those words that sounds just so cool…
Similar is the French for potato, pomme de terre. “Apple of the earth.”
For my pick I’ll go with another french term, menage a trois. (Sorry about the lack of accent marks)
Schokolade. German for “chocolate.” It’s just a really pretty word to say… which you don’t really expect from the German language.
And once again we see the wonderful adaptability of English, which has been known to follow other languages into alleys, hit them over the head, and go through their pockets for loose vocabulary. 
The Arabic Insha’Allah إن شاء الله, correctly defined by Wikipedia as “God willing,” but in my experience it’s used in Muslim countries as the answer to any yes or no question.
And the Yiddish meshugas (משוגעת ), which I’ve also seen spelled mishigass, which is the noun form of meshuggah, and often used to mean “your own personal form of insanity” – “Well, he’s on the SDMB 5 hours a day, that’s his meshugas.”
Zimt, German for cinnamon. I don’t know why, but I love that word.
zimt, zimt, zimt, zimt
In Spanish, it’s *quinientos/i] – kee-nee-EN-tos. Also fun to say.
It had a revelation in my 6th grade German class the day I learned there was no direct English translation for the word ‘gemutlichheit’. It was that day that I discovered that any given language doesn’t necessarily encompass all known things.
For favorite word to say I have to go with the French word for ‘building’, l’immeuble.
For shear efficiency for this humble traveler you can’t do any better than the Ladakhan word Jule (pronounced Joo-lay). It means ‘hello’, ‘goodbye’, ‘please’, and ‘thank you’.
What’s the Arabic for “…and the creeks don’t rise”? 
I became acquainted with this word in my first Finnish sauna experience too - to my ears it sounded like “löuluä” (LOEU-lew-ae). I thought it meant “more water on the hot rocks”, because every so often people would start chanting “löuluä, löuluä!” and any non-Finn had to get their arse out of the sauna or be boiled alive. It’s a beautiful word, especially when shouted by a choir of burly, naked men.
From the Sanskrit: karmadharaya
“blacksmith” is one. (A word made up of an adjective and a noun.)
And from the French: Merde!
I like the Japanese word どうも (dōmo), which has a wide variety of meanings. Literally, it means “very,” but is used as a greeting, a mild apology (for putting someone out) and/or a casual way of saying thanks.
The Thai Sawasdee seems to have that universal smoothing-over function too. Basically a greeting, but it can also be used whenever you’re at the sharp end of a potential offence-giving situation, and need to think of something to say in a hurry.