Toolbars clutter your browser window so if you actually install one for the long run it’s probably going to be a very good one and the WolframAlpha toolbar might just be a good choice. Wolfram Alpha recently released an official toolbar for Firefox. There’s also a Wolfram|Alpha extension for Chrome which was released earlier this year, both the toolbar and the extension let you search anything on the site without visiting it.
The Firefox toolbar has added functionality compared to the Chrome extension. While the Chrome extension only allows you to search Wolfram Alpha, the Firefox toolbar lets you search Wolfram Demonstrations Project, Wolfram Math World, Wolfram Mathematica and A New Kind Of Science. The Firefox extension also has five buttons that link directly to Wolfram Alpha resource site.
The Chrome extension is very minimal compared to the Firefox toolbar allowing you to search Wolfram Alpha only. You can choose to open search results in a new tab or the same tab from the extension’s options.