What exactly does one do with Rainbow Sand?

[raudf]

Well then you just stare at a random spot and hope it is the right spot.

And then Neopets will create a RE around the invisible sand in which your neopet smacks you upside the head for staring at it for so long. Personally, I think they were created for the soul purpose of me creating the most boring and annoying gallery around.. if I wasn't so darned lazy!

[Iron Chef Tacobell]

Being from East Tennessee, I'm kind of partial to the Orange Sand (GO VOLS!!!). I also like the Rainbow Sand and the Glowing Sand. But like most invisible items, the Invisible Sand serves no purpose. Its just an empty bottle, dagnabbit!