One of Firefox 3's newest (and most revealing) backend features is its built-in usage tracking—it keeps a running tally of how often you visit a web page over a period of time, which informs the Smart Location Bar's suggestions and creates things like smart bookmark lists of "Most Visited" sites. Smarter features informed by your behaviour are great, but checking out the raw data can offer a whole lot of insight into where and how you spend your time online. Exactly what site have you visited the most since you installed Firefox 3 and how many times did you go there? Here's how to find out.

Windows/Mac/Linux (Firefox): WebMynd, a free add-on for Firefox, makes it easy to browse through web pages you've visited or specifically "webmarked," whether they're static or dynamically generated. Although you can tell WebMynd not to monitor certain pages and turn its history noting on and off, the add-on generally works as a background service, taking snapshots of the pages you visit. Hit the WebMynd button and you can see thumbnails of those pages. Click on the thumbnails and you get fully browse-able snapshots, with links, images and other data preserved. For hunting down links and images on pages that change pretty frequently, or just getting a more easily-navigated history, WebMynd serves a purpose. WebMynd is free to download, works wherever Firefox does, and lets you browse a week's history at no cost; $US10 and $US20 subscriptions get you six months or a year's worth of snapshots.

The Google Operating System blog has a helpful, quick guide on how to enable Google Web History for more than just Google searches without having to make the usual Google Toolbar installation, using JavaScript-based tools like Greasemonkey for Firefox, Trixie for Internet Explorer, and Safari, Opera, and Konquerer (KDE Linux) also. You still need to be logged into a Google account to enable history tracking, but it could be a real help to those using alternative browsers for which the Toolbar isn't offered. And while many users certainly still have their privacy concerns about Google knowing everywhere you've been browsing, disabling the non-Google portion is as simple as turning off the script.

Windows/Linux: Free beta program IM History offers a web-synced way to store instant message chats across multiple computers, and operating systems, from a variety of chat clients. Right now, the service supports AIM, Yahoo, MSN, Skyp, Trillian, and a few other clients, but my pet peeve is Pigin supported only in Linux, leaving dual-booters like me in the cold. That aside, once enabled, IM History lets you access your chat history and contacts from a web interface, and being able to search chats from across platforms—to find, for instance, a link sent long ago— is where many users will find this app convenient. IM History is a free download for Windows and Linux.

Apparently the tradition of great engineers not having college degrees goes back 2,500 years. Harvard classics researcher Mark Schiefsky has shown that many great technical innovations of antiquity, such as the balance and steelyard, were created by craftspeople with no theoretical training in mathematics. A steelyard is a balance with unequal arms, whose operation is based on ancient mathematician Archimedes' law of the lever. Schiefsky poo-poos the idea that you need a fancy law to make a steelyard, and in fact has proven that steelyards were in use long before Archimedes explained it.