This is a nice, quick, visual and surprising effect that is easy to do.
It's one of those
quirky little oddities that you would want to fit in somewhere then move on to something else.
The block can be fully examined before and after the effect and the wand can be casually
inspected after the effect but I wouldn't let anybody mess with it for too long. Best to just move
on. One of the only draw backs to the effect is the getting into it but it's not that bad.
There isn't a demo video on this site but look one up on YouTube. If you like what you see, get
it because you will be able to perform the effect just like that in a matter of minutes.