From Mashable, “10 Essential Design Tools for Social Media Pros.” A few to note:
5. MockFlow: http://www.mockflow.com/
MockFlow is a versatile tool that enables you to quickly render functional website prototypes without a big time investment. There are also real-time collaboration and note taking features built into the platform.
7. Campaign Monitor: http://www.campaignmonitor.com/
“Campaign Monitor is an intuitive e-mail marketing application created for designers. It has excellent tools for designing professional HTML e-mails, creating and managing e-mail campaigns, useful e-mail analytics, and more,” says Jacob Gube.
8. Proposable: http://www.proposable.com/
He recommends Proposable, an online tool that allows you to build highly customized, branded presentations. A Proposable account incorporates an asset library (which can include rich media like video), a variety of templates, and a comment management system for real-time feedback.