This reminded me of all the expressions I've one through in my life. In elementary school, "DUH!" and "WHATEV" were really big (complete with "W" sign with your fingers), then when i moved to California 6 years ago, I was using "SICK" and "DUDE" a lot. Now there's sheesh, geez, omg, el-oh-el, wtf, just sayin, and many more.
Expressions from other cultures are even better - "bloody ____", "bollocks", "jologs", and many others. Expressions are either made up words or ordinary words made into expressions, right? Hmmm... so does that i mean we can just throw out words like "ahh, toilet paper!!!!" in a moment of frustration? or "MACAROON!!!" in a moment of victory? Oh the possibilities.
What is a widely used expression/saying in your country?