5. Lumosity, San Francisco, USA
Also in San Francisco, the Lumosity HQ has a library full of antique books, and a secret doorway in a bookshelf. There is also a bar within the offices. The bar sounds nice, but to be honest, they had me at the secret doorway.
6. Inventionland HQ, Pennsylvania, USA
These headquarters in Pennsylvania contain a series of mini offices within them, each with their own theme. From the cave office to the pirate ship, each crazy setting is designed to foster more creativity within the team.