It's a little ditty I hope you too will enjoy...
Hooray, hooray, it's the first day of May! For Outdoor Intercourse begins today!
I thought it was some sort of clever old limerick type of legend. But in hunting around on-line, I found many blogs had stories of grandparents and parents who used to call and give them this unique May Day greeting.
Then I stumbled over this article from the newspaper at Western Washington University. (Though they claim Outdoor Intercourse Day is actually May 8th, so there is still time to make your plans!)
Coincidence that this is where I grew up?