I once saw the American comic Sid Caesar doing gibberish in various foreign accents, which he did very well. (In case you don't know, this means "talking" in another language, without actually using real words.) But then the host, who had singled out a Japanese man in the audience, asked him to talk to the Japanese man in Japanese gibberish. The audience thought it was very funny, but the Japanese man just looked puzzled, because, of course, he couldn't understand anything, and it probably didn't even sound like Japanese to him.
Have you heard anyone speaking gibberish in the accent of your country? Did it actually sound like someone speaking your language? I heard a Spaniard singing a gibberish country Western song that sounded absolutely authentic.
This reminds me of the skit on "Whose Line Is It Anyway?" where two performers are supposed to "talk" in a foreign language, and then a third performer "translates" for them. The funniest part is when someone utters an incredibly long gibberish sentence, and the translator says something like "No".
Lazar, using foreign language gibberish is frequently used in comedy improv. People often throw in actual foreign words and phrases, but it's really impressive when they can avoid real words and still sound as if they're speaking the language.
Some years ago, I saw a funny practical joke on TV (the program was called something like "TV's Bloopers and Practical Jokes"). It seems Johnny Carson was known to have said that he had a hard time understanding people with posh English accents. So when he was in England for some special occasion, a group of actors were hired to attend a party he was invited to, and speak posh gibberish to him. They used enough real words to convince him that they were speaking normally, with enough gibberish to make them incomprehensible (to anyone, not just to him). It was great to see Johnny Carson being polite and seriously trying to hold up his end of the conversation, even though he had no idea what anyone was saying.
I've never found gibberish amusing because it is too obviously fake in most cases. People speaking gibberish often don't know anything about the target language of the gibberish and may not even be multilingual, so they make mistakes that betray their native languages and make it obvious that they don't know the target language. To people with no significant exposure to real languages other than their own (such as most Americans), I suppose it sounds funny, but once one has studied other languages formally, it loses its appeal.
I can understand why the Japanese man was bewildered: what he was hearing probably sounded much like English to him, and so he couldn't understand why anyone would call it Japanese gibberish.
I think that gibberish was more popular in the past when people had less exposure to other languages and cultures. Today, it probably still works among the aforementioned groups who still lack such exposure. But I don't think anyone would find it very funny in, say, a nightclub across from the UN.
Oddly enough, I, who have had a lot of exposure to foreign languages, still find it funny when it's done well.
I think it's an interesting way to hear how your own language sounds to others. If someone is actually speaking your own language to you, it's difficult to separate the meaning of what's being said from the sound of it. But with gibberish, it becomes very clear.
How does gibberish actually work? I know 2 people who always speak it and I don't understand a thing!