Azendoo: Task management that app that makes it easy to organize by project and share tasks between team members, as well as collaborate with clients. You can also associate files from Evernote, Dropbox and Google Drive with your projects.
Evernote: Virtual workspace and note taking application that allows you to create text, photo and audio notes and makes them available on any device. This is my key program for storing and organizing notes and having everything I need at my fingertips. I use Evernote as much as I use my email. Sign up here.
Freshbooks: Financial tracking app for small businesses and freelancers. This is an outstanding tool for tracking time and expenses as well as generating invoices.
IFTTT: Web-based application that connects other web-based services together. For example, IFTTT sends any Tweet that I favorite to a new note in Evernote so that I can keep it long-term. IFTTT helps you consolidate the many services you use and not lose track of what you are creating or consuming.