I was listening to grade school/high school/college students talk, and every other word is “like,” and I wonder if there is an equivalent in other languages or cultures…
Israelis definitely use k’ilu (‘it’s like’, or ‘it is as if’) the same way Americans use ‘like.’
Chinese people say nega quite a lot.
I don’t know much about the Hawaiian language, but it seems like a lot of Hawaiians use “da kine” about the way American teenagers use “like.”
(That’s assuming you’re talking about when the use “like” as a filler word with no meaning, as opposed to using it as a real comparator)
I can confirm the Chinese “nega.” It’s used almost like “like.”
Previous thread:
I’ve heard people speaking in Hindi use matlab and people speaking in Bengali use mane as filler words similar to “like.” The mean something like “I mean.”
In Czech, “prostě” (“simply”), “jako” (“like”), and “tak” or “takže” (“so”) are all used as a filler word the way “like” is in American English. The particularly adept can fit “prostě” in four or five times in one sentence. “Ty vole” or “vole” (“you ox” or “ox”) is also used, but that’s probably more the way we use “man” - as an informal form of address, an exclamation, etc.
Not particular to young people, but in Dutch - as in English - plenty of filler words, are used. For example:
dus “so”
of zo “or something”
weet je (wel) “(do) you know” - Wikipedia notes that Dutch English speakers use “you know” an awful lot.
That’s excluding the extremely common non-words such as ehm and uh (basically, errm or uh).
In French, many people pepper their speech with “genre” which is more or less the same as the Valley-speak “like”. Also : “tu vois” (“you know/you see”), “je veux dire” (“I mean”) and ending their sentences with “quoi” (“what.”)
J’veux dire, c’est genre difficile de s’en empêcher à l’oral, quoi. Genre on s’en rend même plus compte, tu vois ? 
Japanese have a zillion examples, both slang and not slang. A lot of it, like all Japanese, is dependent on the relationship between the speaker and the listener. Also, a lot more of it is “female language” which is something to watch out for if you are a guy and your teacher was your Japanese girlfriend or other female.
It’s probably a Québec thing, and maybe even limited to Montreal, but lately I’ve heard people speaking French and using the English word “like” as a filler word.
C’est like, bizarre à entendre!
In Spanish a lot of people seem to use “este” as a filler word (often drawing out the second syllable until they’re ready to say something)… its literal meaning is closer to “this” than “like” though.
I think I heard Grant Barrett on A Way With Words say that there was a recent study that suggested that filler words actually are beneficial in that listeners tend to retain information much more when the speaker is using filler words.
They must be great at linear algebra.
Really? The only thing I retain when I hear someone saying “like” constantly is a passionate desire to wallop them over the head with a frying pan.
Arabs and other middle eastern and south asian languages use “yani”
“Da kine” is not a filler, it’s a placeholder for a noun or verb.
“Put da pencil in da da kine.” = Put the pencil in the cup. Usually accompanied by pointing or nodding at the cup in question.
If it were used like “like”, “She, like, was soooo, like, upset!” would be “She, da kine, was sooooo, da kine, upset!” and that’s pretty awkward. Pidgin speakers are far more likely to use “like” in that usage than “da kine.”
If anything, “da kine” would be substitued for “upset”: “He told her he was cheating on her and she got so da kine!”
Something of a tangent from the OP, but: pravnik’s post reminds me a lot of the way some American subcultures use words like “hoss” or “dog” to refer to listeners belonging (approximately) to the same social stratum.
Kobal (or any French speaker) … in this usage, does the final -re in genre tend to get weakened, or even unpronounced?