Small Blue Printer

Now this is interesting: Small Blue Printer allows you to put together a basic floor plan on your web browser, no software download or experience necessary. It even offers a "3D" view. Now, it isn't a full-blown architect program like 3D Architect or a modeling program like Sketchup and so it's features are limited; but if you want to experiment with basic layouts for your dream home or castle, it'll do just fine.