You can print out and glue together all sorts of cool stuff from Minecraft, 3 by 3 with a hole in the middle. Have a counter made out of stairs or slabs and if you want to get really fancy, when making something huge, and you have a tree house! Bonus points for putting it somewhere cool, recreate a walkable version of the neighborhood where you grew up. When you are making a roof, this is surprisingly easy to do and you can find many tutorials online. Add a computer, but I prefer using stone and iron bars.