Squidly.ink - Comment and collaborate directly on any website.

Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.

Evrybo - Free design collaboration and prototyping tool

Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.

Joomla - Joomla! is the mobile-ready and user-friendly way to build your website. Choose from thousands of features and designs. Joomla! is free and open source.

Basecamp - A simple and elegant project management system.