A yo-yo
Image credit: <a href="https://www.flickr.com/photos/ecalabuig/">Enrique Calabuig</a> [<a href="https://creativecommons.org/licenses/by-sa/2.0/">CC BY-SA 2.0</a>], via <a href="https://www.flickr.com/photos/ecalabuig/5151159056">Flickr</a>

Yo! Check it out. Today is National Yo-Yo Day, because it’s the birthday of Donald F. Duncan, Sr., the eponym of the Duncan Toys Company—best known for its yo-yos. Duncan did not invent the yo-yo, which has been around in one form or another for millennia, but he certainly did help to popularize it. And, today (June 6) only, you can buy genuine Duncan yo-yos for 50% off using the coupon code YOYODAY50! (If you’ve had your eye on a purple HaymakerX, which normally retails for a whopping $119.99, this is your big chance to get it for a mere $60. Jeepers.)