If you do a lot of casual research on the Web, Hyperwords might be the perfect tool for you. This free Firefox add-on turns every word on a Web page--even in Web mail programs--into a link to reference and shopping sites. It also adds a Hyperwords toolbar that you can customize or remove completely.
Hyperwords is very easy to use. Just select text on a page and choose an option from a pop-up menu that includes Search, References, Translate, View, Copy, Go, Email, Shop, and Settings. (You can also right-click selected text to open the Hyperwords menu.) This functionality gets annoying in Web mail pages, but you can select Settings from the menu and control how the pop-up appears. For example, I chose "When you select text and hit Enter" to launch Hyperwords and this fixed my Web mail issue. You can customize practically every other aspect of the program as well.
This Firefox add-on almost contains too many features. I tested the program for over an hour and still didn't sample all of its offerings. Its Search function pulls results from many sites. A basic search on "energy," for example yielded discussion threads, a how-to-pronounce page, Google results, and more; choosing Shop yielded seven sites simultaneously, including Amazon.com, NexTag, PriceGrabber, and Craigslist.
To translate any text just select it, choose Translate, and pick the language combo that you want. I can't judge the accuracy of translations to Arabic or French, but when I translated a Spanish page on cooking, this is what I got: "Sometimes to be one better and faster cook means to have some tricks of kitchen under the sleeve. ... Necesitas to increase your culinaria wisdom? Lee next and pon in practice intelligent recommendations to apply in your kitchen."
I wouldn't recommend Hyperwords to a professional writer or researcher, since the reference sites that it pulls from include general sites like Wiktionary, not formal references like Merriam-Webster. But in general, Hyperwords could be useful to students or people who enjoy doing casual research on the Web.
Note: Hyperwords installs directly into your Firefox browser. Click Download Now to install it.