Form Editor is a free and open source form builder for Umbraco 7.
By placing the form layout and submissions directly within the context where it's used, Form Editor takes a radically different approach to form building than e.g. the official Umbraco Forms.
The Form Editor mantra is "Simplicity over flexibility". The simple and intuitive editor experience is in focus. All the same, Form Editor offers a lot of advanced features, allowing the editors to create quite complex forms when needed.
Archetype is an awesome property editor for Umbraco 7. In short it wraps all other property editors in "fieldsets", making it possible to build modular and responsive websites without sacrificing the great editor experience.
I'm part of the core development team that keeps Archetype up to date and working across Umbraco releases. It's a hugely popular project within the Umbraco community with tens of thousands of installations across the world.