GUI prototyping tools

Recently I was looking for a GUI drawing tool, I found two free solutions

1. The pencil project open source GUI drawing tool available for all platforms, including widgets for phones
2. www.draw.io online drawing solution including GUI drawing and UML diagramming

Domain driven vs service oriented architecture/design

Domain driven design and service oriented design are opposite approaches, while service oriented approach is more stateless (SOA) and more procedural programming like, the domain driven approach is more stateful and object oriented.
The best practices in each case tend to become anti-patterns in the other case.