Ask HN: What is the best Design Mockup tools?

Balsamiq offers both site and iX mock-up items:

Take a look at WireframeSketcher. It's an Eclipse plugin for Eclipse, Aptana and other Eclipse-based IDEs. There is a Mockups Gallery website with templates for iPad and iPhone apps that you can make use of.

http://wireframesketcher.com

I have been looking at mockflow as something I want people here to use instead of a scribbled, stapled pieces of paper.

If you prefer working on an iPad check out: iMockups or Keynote Wireframe Toolkit

Pen & Paper! BEST OF BEST