You might have seen this kanji being used for expressing a deeply humorous situation at places, -- 笑. I myself use: 笑 笑 笑.
In principle because we abuse lol the most, I think it comes to category of selfie and twerk, but in abusive usage perhaps lol will win.
Here is why its called as emi, first of all -- which is my mother's name: Amy, Emi, Emmy etc not Emma. This is the reason I remember this kanji, also I make her laugh out loud a lot with my joking nature. She used to get irritated a lot @my jokes, but now I am getting irritated when she laughs at my joke.
emi -- 笑, is said as emi in emission. And I see that this is a combination of two kanji, one is a kanji which is "bamboo" --竹, and there is a kanji which is "sky" or "heaven" -- 天.
Does that combination make you laugh? Bamboos in Sky. Ha ha ha ha ha ha ha ha ha ..
OK stop it. Use lol for compactness.