FastestFox is a really popular - and useful - add-on for Firefox, so Chrome users will be glad to know that it's available for them too. Although it doesn't have exactly the same functionality (and the name isn't quite as catchy), FastestChrome is a valuable extension for any Chrome user.
FastestChrome works by adding a range of extra search functions to your browser - when you highlight a word or phrase a pop-up bubble appears with extra search options. If you click one, FastestChrome will automatically search for the terms in question using the service you chose - from Twitter to YouTube and OneRiot to Bing - and display the results in a new tab. If you hover, you'll get a short Wikipedia definition of the word or phrase.
The FastestChrome settings appear in a new tab, which makes them easy to see and modify. You can include/exclude a variety of search engines and tweak a number of other settings, mainly ones related to what appears when you roll over a highlighted word. FastestChrome doesn't have the download feature of its Firefox cousin, or the qLauncher function, but as I felt that these were two of the apps weakest features, you're not missing much.
FastestChrome adds extra searching abilities to Chrome and makes for a valuable extension.