I taught myself to juggle. Although I’m terrible at it, a side effect was when I’m at the grocery store, I can toss small items out of the basket with one hand and catch it with the other hand without looking, then setting it on the conveyor belt. It works great for cans, spices, and yogurt which I buy 30 at a time.
I can French braid my own hair.
Type. Light a Zippo on my jeans. Tank in World of Warcraft.
French knitting.
I do blind contour sketches. It’s a really good drawing exercise in which you follow the outlines of an object with your eye as you draw, but never look away from the object to check the paper. Sometimes the sketch can be shockingly accurate.
Knots. Bowlines, sheet bends, half-hitches, square knots*, trucker hitches, slip hitches, and even the occasional hangman’s noose, no eyes required. It’s rarely useful, but I am a theatre technician, and so am sometimes needed to tie knots in semi-blackouts.
*Just say “no” to square knots, kids. They kill people. For decorative purposes only.
Oh, and I can finger-knit without looking.