4. The Mirrorcube Tree House Hotel - Sweden
Part of the appeal of going on holiday is the anonymity, the freedom to step outside your normal behavior because hey, you're just doing to be disappearing into a crowd of faceless tourists anyway. But what if you could actually be invisible while on your vacation? That's a pretty tall order, unless somehow you've managed to vanquish Harry Potter and steal his invisibility cloak, in which case you're probably not reading this. But the Mirrorcube Tree House Hotel has come as close to invisibility as is humanly possible. This hotel has a number of fun tree house rooms that you can stay in, up where the birds live in the forests of Sweden, but their gem is the Mirrorcube room. It's a 4x4x4 meter cube covered in mirrors that does such a good job of blending into the scenery that they've had to add infrared coverings to the walls so that birds don't accidentally fly into them.