Autocopy – The name pretty much says it all. Instead of having to hit cmd+c (or ctrl + C for our Windows readers), every time you highlight text it automatically copies it to the clipboard. If you don’t want it on 100% of the time, you can toggle it on and off in the bottom-right of the browser. Better Gmail – A must-have for any Gmail user. Maintained by the legendary Gina Trapani of Lifehacker, Better Gmail adds some killer features that would make any developer at Google scratch their head and wonder “Why didn’t I think of that?!”. Keyboard macros, saved searches, right-click preview views and integrate Google Reader to name a few. (The keyboard macros are enough of a reason to install this little filly, in my humble opinion.) Better GReader – Another gem from Gina for Google Reader. Add feeds to GReader and bypass the default add page from Google, make the most of the reading area and take advantage of some great keyboard shortcuts, to name a few. No Squint – Finding yourself going cross-eyed form leaning too close to the monitor? No Squint can fix it. Specify a percentage to show all text that’s larger than the default for your screen resolution. You can either make all sites a default size, or only specify a few with different font sizes. Remember the Milk for Gmail – If you’re a fan of the todo list application Remember the Milk, you’ll love this extension. Fully mange your todo items inside of Gmail, instead of having to trek over to the RTM website every time you want to check off a task. You can also quickly assign emails as tasks. Very slick. Shareaholic- An indispensable extension for those who do a lot of social bookmarking with digg, del.icio.us, twitter, or maintain a tumblelog. In one click you can share the page you’re on with the previously mentioned services (plus a few more) without spending any more time than you have to away from the article. LeechBlock – If you’re feeling a little vulnerable to the addictive qualities of certain websites, use LeechBlock to literally force you from visiting them within a certain time period of the day. No joke. Not for the faint of heart, or those with problems with authority. Read it later – Don’t have time to really focus on an article you’ve found? This extension will enable you to quickly save the page you’re browsing until you’re able to read it. Once you’re ready to read your saved articles, the extension will open the articles in new tabs with the click of a button. Scrapbook – Much like the Read it Later extension, Scrapbook allows you to quickly save pages for later reading. However, it has a few more great features, like taking whole snippets of pages (like Google Notebook), searching within snippets, saving whole websites, and you can even organize the snippets like bookmarks. Perfect for researching or in-depth bookmarking. Meetimer- Meetimer is a great way to get a handle on just how much time you’re spending on various sites around the web. You can group sites into categories (ie. facebook.com = “procrastination”), and track just how much Copy Plain Text- The name pretty much says it all. If you do a lot of writing in WYSIWYG editors (blogging and other word processors), then this extension can come in pretty handy. Copy Plain Text will leave all the bolds, italics and other unwanted formatting when you copy and paste into text fields. Ad Block Plus- For those obsessed with a zen-like minimalist approach to web browsing, this Ad Block Plus will surely keep you focused. Kill annoying banners and ads by simplying installing the extension and right-clicking the banner on the page. Once you’ve clicked the banner, you’ll never see it again as long as the extension is turned on. Gmail Conversation Preview – A nifty little Greasemonkey script that allows you right-click and see the body of the email, without opening it. Simple and slick. Invisibility cloak – Lifehacker’s solution to blank out certain time-wasting sites that kill productivity. This is a much smaller version of LeechBlock. Add a second inbox to your Gmail account – Quickly and easily toggle between Gmail inboxes. Perfect for those with a business and personal email accounts at Gmail. FEBE – On the surface, FEBE will quickly and easily backup your Firefox extensions. But the fun doesn’t stop there. You can also sync multiple computers with the same Firefox extensions, and even set up automatic backups, ensuring that you’ll never lose your Firefox configurations again. del.icio.us bookmarks – Save, search and share your Del.icio.us bookmarks easily inside of Firefox. Browsing your bookmarks is especially easy with the del.icio.us sidebar. Googlepedia – I find this extension extremely valuable for getting a more holistic Google search. Googlepedia splits the Google search results in half and shows the relevant Wikipedia page for the search alongside the Google results. Errorzilla Mod – This extension is pretty nifty for troubleshooting error pages that you might come across, giving you the Google Cache, Wayback Machine, Whois, and tons of other useful information about the site and page in question. Pageaddict – Pageaddict simply shows your internet usage by website. It’s not as intrusive as Invisibility Cloak or LeechBlock, but it can provide a helpful look at where you really spend your time online. urlfixer – I can’t tell you how many times I’ve typed in “gmail.cmo” to get a frustrating error page. Instead of having to perfectly type in every url, urlfixer can usually guess where you’re trying to go, and will send you there anyway. Colorful Tabs – This extension is deceptively useful. Much like office file-folder tabs, colorful tabs gives a color to each tab opened in Firefox. Quickly find which tab you need without having to read it. Faviconize Tab – Save some serious tab bar real estate with Faviconize tabs. With a simple right-click, you can shrink each tab to only the size of the favicon (16×16px), giving you much more room for open tabs. Google Notebook- Google notebook is another bookmarking tool, except it can save whole excerpts from pages, images and links. Quickly save all parts of a page into an digital “notebook” for easily collecting. Not quite as nifty as the Scrapbook extension, but definitely a contender. Dictionary Tooltip – A perfect companion for any writer. Just highlight any word and hit Ctrl + Shift + D to see the word’s definition, without having to open a new window.