Redditor BillyAppletini surprised a friend with an "Imperial CAT-AT (All-Terrain Armored-Transport)" -- a cat-condo/AT-AT walker. His Imgur gallery , which documents the build, has some rudimentary plans as well.
I wouldn't consider myself a great woodworker or an artist - but I will take credit for being committed to a joke. I wrecked my house for a month building this, which was about 27 days longer than I wish it would have taken. The trickiest part was keeping any of my friends from coming inside my place for that whole time - I knew they wouldn't be able to keep it a secret!
The inside of the CAT-AT has a fully furnished luxury cat condo.
I was originally going to forge an Amazon receipt and make it look like my buddy's cat ordered it on his Amazon account and have it delivered while he was at work, but enough was enough - when it was complete, I had to get it out of my loft and clean up.