Google has a cool new Toolbar out and I am downloading the application now. Be sure that you read there disclaimer. At least they are very open about how the Toolbar works and what it is doing. I think the most interesting thing about the disclaimer was that they tell you that you will be sending information back to Google.
I have had version 1 on my browser bar for a long time so it should be interesting to see what they have developed with version 2. [Google]