What I have here is something called ferrofluid, and if I put a magnet under it, it's able to make these really weird spikes. Then if the magnet is pulled away, the spikes all magically disappear, and this honestly kind of blows my mind every time I see it. What I also think is interesting though is what happens, if I put it directly onto the magnet.
It doesn't really spike like before, but it becomes super slippery. It's actually able to hold itself up sitting on top of the ferrofluid, and it glides around, with what feels like no friction. Personally though, my favorite thing is what it can do on paper.
It's able to slide super effortlessly, and it feels like the smoothest marker I've ever used. The line that it makes is also shockingly clean, and I just think it's pretty cool.