Couldn’t find a topic about memes in/about Japanese so here’s one. Show me your best memes. I’m waiting! 
The phrase for “to count on your fingers” could literally be translated as “to break your fingers” (指を折る)
Not to be a downer, but I think it comes from the meaning as bend/fold not break. 
これを作った。だけど、正しいか正しくないかどうか分からないんです。
運河 (うんが) is the word for canal
Well, there’s this thread at least. It’s not about Japanese per se, but there are some related memes as well.