Yeah, this is actually a thing.
And no, I don't have one, that is just a flipped picture of my own tree. This year especially, this 'hot' new trend is popping up all over online stores.
Here's what you need to know:
The upside down Christmas tree can either hang directly from the ceiling (off a beam or a specialized hook) or you can buy a fake one with the traditional stand, only the tree is flipped upside down.
They are not cheap. You can find prices ranging from $200 to $2000 for one of these bad boys.
If you have one hanging from the ceiling, it can be space efficient. But then you'll have a pile of presents in the middle of the floor which might look silly. On the other hand, your cat won't be able to attack it.
If you hang a live tree upside down, prepare for it to die quick - you can't water an upside down tree, can you?
In conclusion, I think it's definitely a cool and unique idea, but personally I don't see the appeal. This year I'll be sticking with my traditional grounded Chritsmas tree.