Southwest Airlines is offering $67 economy tickets on select domestic flights with an offer it's dubbed the "Trendiest. Sale. Ever." The sale is a nod to the internet meme popular with Gen Alpha, where people shout the numbers "6-7." The saying has become popular on social media, but its origination remains unclear.The meme appears in the song "Doot Doot (6 7)," a song by rapper Jamille Edwards, known as Skrilla, that went viral on social media. Since the song became a viral sensation, the saying has taken ...