Well, I just got the message that the theme this week is "Treehouses"... needless to say, I thought it was super cool!
It made me think of this one place right away. Cedar Creek Treehouse at Mount Rainier:
Also, you need to keep up with the magazine "Ready Made". They have a great print magazine, but the website is really amazing as well.
They have some cool things like "Grown Up Treehouses". Always fun! It's something I hope I can one day have in my own home. I love a good hide-out, and my blanket tent isn't as fun as a treehouse!!