The JAB Workbench Freeware Libraries include the JAB Recipe Library, which contains numerous GUI Widgets and a framework for connecting to a SQLite database using a Java applet. Many example projects are provided, divided into various packages, including GUI Examples, Database Access Examples, and Advanced Examples.
MockMockWeb is a Heroku-ready Node.js-based Web application server which allows you to mock up a website in seconds. It allows you to instantly launch a website which sends an empty page (with status 200) to any request/URL and edit any page on the spot. You can also edit the layout shared throughout your website. It lets you build a mock (sometimes real) website in a request-driven interaction.