Recently, political website pointed out that Pharrell Williams' "Because I'm happy" has become an extremely popular, but unlikely protest song worldwide. Last month, I also saw him on German television explaining that the idea for the song came to him when he realized how he didn't like songs that tell people they have to be happy. You know, like "Don't worry, be happy":
Your landlord says the rent is late
He may have to litigate
But don't worry, be happy
I have personally always detested that message (anybody who tells me to chill when I'm about to get kicked out of my apartment had better be able to run fast). That's really what makes Williams' message so inviting – it's not bossy. He simply asks you to "come along if you feel like that's what you want to do."
In addition to some of the "protest" versions you can view under the link above, there is the 24-hour version, a Star Wars version, and a slew of non-protest localized versions – including one from Freiburg, which made me very unhappy because we were planning to do our own.