Giko's favorite phrase is "ITTEYOSHI!!"

　　＿＿__＿∧∧　　 ／￣￣￣￣￣￣￣
〜'　＿＿__（　ﾟДﾟ）＜　　逝ってよし！！
　 ＵU 　 　Ｕ U　　　 ＼＿＿＿＿＿＿＿

This often gets translated as with "Go and die" or "Kill yourself" or "Fuck off". All of these translations seem to be not getting the jist of the expression, though, since "Itteyoshi" is a play on words: http://4-ch.net/nihongo/kareha.pl/1101446156/55

> If you're a japanese and hear it without seeing the chinese character used in it,
> then you will think it means "you may go" ,or "go away" in a less dominant imperative.
> But if you read it while seeing the chinese character,
> it means "you may kill yourself" or "kill yourself".
>
> You can use this phrase when someone posts a silly remark or
> asserts something with lame evidence.
>
> note: "行く(iku)" means "to go", "逝く(iku)" means "to die".