ToysmithEuler’s Disk – Create A Hypnotic Display of Light & Sound- Science Desk Decor for Home and Office – Physics Toys for Adults & Kids 8+

The steel disk is thick heavy and machined to spin well and for a long time on the concave mirror as the disk contact frequency increases as the disk spins and tips on the mirror. Gift for 6 year old boy or older. Conservation of angular momentum impresses everyone.

Who says anyone is too old to enjoy cool stuff like this?! I can't even believe people gave this any less than five stars! Not sure what they were expecting, and apparently some people were spinning the box it came in, I guess, or trying to spin the mirror on the disk maybe, or spinning themselves instead of the disk, ahahaha, who knows, but if you like absolutely cool gadgets that serve no other purpose than being COOL GADGETS then you will LOVE this thing!Here's a tip so to not be disappointed, thinking this was supposed to be Thor's Hammer that will make you fly or something -- just go to YouTube, look it up, watch the video, and if you say "how dumb and dull" then don't buy it -- and certainly don't buy it and then say how dull or dumb you think it is! If, on the other hand, you said, "Oh, yeah, totally cool" then TOTALLY BUY IT.It does EXACTLY what it does in the video -- put the heavy disk on the mirror, give it any kind of spin, and be amazed as, just when you think it's going to stop spinning......it doesn't stop spinning! Get even more amazed at the hypnotically cool display of colors (which can be changed in pattern, by swapping out the magnetic covering pieces you can put on the disk, and can be highlighted by shining a flashlight on it, especially in a darkened room) and then be amazed again when it still just WON'T QUIT!!! Amazement ensues even more as it finally begins the wind down stage, seeming to spin crazy fast, and faster and faster, and making an increasingly louder sound as if building up to a detonation and then amazement flies off the charts as it reaches a crescendo and suddenly, BAM, silence!You don't even have to be smart to realize you just saw something scientific and be all like, WOW, COOL!!!!Yes, I know, I just described the video, right??? Because that's what it DOES!!! So, you like the video, you say, oh I definitely want to try that, because that just can't be real, and you buy it, you spin the disk, you get the show, and you love this thing!Even more cool is every new person can't believe it -- ask anyone how long they think it will spin and nobody gets that this thing just spins SOOOOOO long and, yeah, tons of fun. Never has disappointed anyone, and it's so unassuming, just sitting there.....the curious will ask, "Hey, so what is that," and let the magic begin. I think it's so awesome when we can see something that isn't easily explained by what we normally see -- we know a spun coin will soon quit, so we don't expect this big coin looking disk to go on and on and on! Makes people feel young again, to have that taste of mystery.My office has plenty of these kinds of gadgets, but this one is the coolest and clients are always entertained, as well as my staff, haha, and all in all people love my office, which is great because you want people laid back and happy when talking to the boss, and it just makes for a relaxed and interesting space. Office gadgets rule!So, if you don't like cool scientific toys that leave people saying, "Wow, I can't believe I just saw that!" then don't buy it. But if you like those kinds of things, then, yes you'll love it -- kids and adults alike are amazed to watch it, and hey, we can all use a bit of wonder in our world, right?This is a purchase you can literally decide before buying, simply by watching it on YouTube. That's the exact product and performance you are getting, and you either like that kind of thing, or you don't, so it's a really simple purchase to make....or not!I found it more cool to own it, than just to watch the video, but then again I like stuff like this, and frankly would like to buy a lot of the other things in related videos. In this age of tech wonder, sometimes the simple old wonders are much more entertaining.As for being a "toy" I would agree with others who have said it's not really a toy, in the sense of a truck or doll or something to "play" with, but more like a science demonstration that passes as a magical trick, since it's so unusual to see, and requires no knowledge (or dull explanation, frankly) of what's happening to be impressed by what takes place. It's not something likely to entertain a child for hours on end, but such is not the point. Besides, the mirror is glass, obviously, and a wrong toss of the coin would shatter it, so not something really to give to a child and say, "Here, have fun!!!" I will say it keeps people of all ages stumped, and they always want to see it again, so it has good use as a cool gadget left out so that you can show it folks, or let them give it a try.It's something for people to experience and enjoy and if that's not worth the small asking price of twenty bucks, then people just aren't making room in life for things that have no purpose but to be awesome, which is a purpose unto itself, of tremendous value, such as having your kids, and yourself, lose the shoes and socks and step in paint and then paint with your feet, making a family footsy collage, and then just making a (controlled, ahaha" mess, for the sheer fact that it can be done, and feels cool.We have lost touch with sensory experience, much to our detriment! So put down the smart phone and tablet and enjoy this actual physical object. Definitely worth the small price of admission for this show!Watch video. Like. Buy. Be happy! Share the joy!I HIGHLY RECOMMEND!!!!

Excellent quality product that demonstrates important physics concepts in a very interesting way.

I bought this having absolutely no expectations but as it turns out, it has been a lot of fun. I just wish that it spun a little longer, it stops after about 45 seconds but it’s still a lot of fun. Grandkids love it.

It's fun because it keeps going and going. Good quality and sparkly.

Really cool, a bit overpriced though

Works exactly as shown in the video simply awesome

Nice to see that Toy again. Been 25 years