A yo-yo
Image credit: Enrique Calabuig [CC BY-SA 2.0], via Flickr

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.)