Ask the Experts: What is the one (third party) application you use every day?

Welcome to June Edition of Ask the Experts – Blog Edition. Today's topic, our third in this series, should generate a wonderful variety of responses:

"What is the one (third party) application you use every day?"

As each blogger on our team answers this question, their entries will appear below as a trackback. Alternately, you can choose to visit your favorite author’s blog by clicking on the links above to read their answers.