Window onions?

Ok, so I saw this on Pinterest and have been skeptical.  I thought I would try it just to see what would happen.  I was also wary because my experience with growing onions is that you can sort of smell them while they grow.    EEww. 
So, green onions used for chicken enchiladas, but this time cut the white bottom part off about 3-4 inches up.  I am trying it with only a few in case this goes wrong.  :D

Here is the "before" pic.  I placed the cuts into a few inches of water.  Now three days later, I am so pleasantly surprised to see that it is already working!  Skepticism be gone, it seems to be working...  I hear that these are unlimitedly harvest-able.