In some sense yojijukugo are the original memes, in that they can be riffed off for humorous purposes. For example, the Japanese idiom for "the strong devour the weak" is 弱肉強食 jakuniku kyuushoku (the meat of the weak is the food of the strong), but you can instead say 焼肉定食 yakuniku teishoku (lit. grilled meat set meal) for laughs, and rakugo comedian Jakusaburo Katsura released an album called 雀肉共食 jakuniku kyuushoku (same reading, but meaning "let's eat sparrow meat together" and referring to his own name).

Just had 焼肉定食 for lunch.

Japanese is a wonderful language for puns. Not only do they have homophone puns (so many homophones) and rhyming puns, but also visual puns like Katamari Damacy 塊魂.

Kind of in the theme of 塊魂, there's a yojijukugo with 4 鬼: 魑魅魍魎 (ちみもうりょう, chimimouryou, evil spirits of rivers and mountains)

I like words where one kanji is changed to make the meaning opposite (without changing the pronounciation)

名演 (great acting performance) -> 迷演 (baffling performance)

国道 (highway) -> 酷道 (road in terrible condition)

There are also some horrible ones like 毒女(独女) and 害人（外人）

Also 休館日 (museum holiday day) -> 休肝日 ("give your liver a rest day" - i.e. sober day)

It's not actually a pun (at least, AFAIK), but interestingly, 肛門 (anus) is an homophone of 後門 (back gate).

I have been wanting to learn Japanese but have been putting it off, you just convinced me that I have to get started learning it already. I love a good pun!

強 and 共 are read kyou, not kyuu

I always joke with my wife that my favorite yojijukugo are 問題解決 and 安全第一 which are literally just "problem solving" and "safety first" haha.

My favorite actual yojijukugo is 点滴穿石 which water dripping on a stone in the same spot slowly wears it away, which just means if you keep doing what you're doing you will eventually make some noticeable progress in the long run.

Russian language has an idiom similar to 点滴穿石 - "капля камень точит", literally "a drip grinds a stone", i.e. small but persistent effort eventually overpowers even the most hardy obstacles

I'd bet that many languages have this idiom. I know it in Latin, Italian and German: - gutta cavat lapidem - la goccia scava la pietra - steter Tropfen höhlt den Stein

Some that I like:

一石二鳥 (issekinichou ; literally: one stone, two birds ; I'll let you guess the meaning (yes, it's very close to an expression in English))

自業自得 (jigoujitoku ; reap what you sow)

自作自演 (jisakujien ; self-made self-staged ; for example, used for the act of creating a staged situation and then acting as if it were genuine)

自問自答 (jimonjitou ; answering one's own question)

自暴自棄 (jiboujiki ; self-abandonment)

自画自賛 (jigajisan ; singing one's own praises)

自給自足 (jikyuujisoku ; self-sufficiency)

自由自在 (jiyuujizai ; free/unrestricted)

(Yeah, I have a thing for the 自◯自◯ ones)

It breaks the pattern but you might also like:

自演リプ (jien-ripu)

Literally it's "reply" together with a term for an actor performing a work that they also wrote. And together the phrase is net slang for sock-puppeting.

> 自作自演 (jisakujien ; self-made self-staged ; for example, used for the act of creating a staged situation and then acting as if it were genuine)

The original meaning was a screenwriter-actor performing the script they wrote, which is a perfectly fine thing to do. It can mean 'sockpuppeting', too, and that other use might be more common nowadays, though.