Best Gadgets, Widgets, Etc. And Why?

Today I have a request for you. I want to know which Vista, OS X or Google Gadgets/Widgets you think are the coolest and why. I am doing some research and would truly value the input of my trusted Lockergnome community on this matter. And if simply find yourself being one of those who really don’t care about such things, then I’d love for you to talk about specific applications instead and why you cannot live without them instead.

My goal is to get a better grasp on what works and what is not working in this arena. Across the board, I feel like usability in tech has been completely left behind and am investigating ways to fix this. This includes OS’, hardware, consumer devices, and so on. But for this experiment, I am simply looking for applications and widgets, nothing more.

Please just post your thoughts in the comment area as email is only for direct questions or other unrelated comments. Thanks everyone and have a fantastic weekend!