My 5 cloud based tools

DropBox allows users a powerful and easy way to store files online for sharing or for backup.

Picnik allows you to upload your own images for editing or send images from the Web directly to your Picnik account where you can process them without them ever touch your hard drive.

Basecamp allows you to save all files and project-related correspondence in one place.  It provides online collaboration and management tools for team members and managers that are accessible from any computer or smartphone

Dimdim provides a place to hold online meetings, conduct Web conferences, and conduct webinars in the cloud.
Zoho file and calender sharing provides a way for users to share access to digitally stores info like documents, multimedia files and calenders