Last month I mentioned several search engines that “cluster” or classify the pages they have found, rather than presenting a plain Google- or Yahoo-style list of results. Another worth considering is Kartoo, which was created by two young developers in France. Like Grokker and some other clustering sites, Kartoo presents a visual map of pages related to your query, with conceptually similar sites bunched together and with links showing which bunch of results is related to which other bunch. Ujiko, another clustering engine from the same company, displays results with a different, dial-like map, and claims to be able to improve its search sophistication over time, as it observes which results you end up clicking on. Each is worth a look.

Mooter, from a company in Australia, produces sparer-looking but otherwise similar conceptual maps of search results. Indeed, its interface is so plain that it closely resembles Google’s original site, before home-page links were added for News, Video, Images, Maps, and Google’s other new features.

The month before that, I discussed the tedious but important obligation to make regular file backups, not simply to avoid being flummoxed by a hard-drive crash but also to preserve information that might be trapped in an outdated operating system. A new service called Carbonite automates this process by copying every file on your computer, or some subset of files that you select, into an encrypted online storage site. You specify what you’d like backed up, and the rest happens automatically. The service costs $50 a year for an unlimited amount of data. It can take a week or more to do the full initial backup, but neither during that process nor afterward does Carbonite slow the computer’s other operations.

And one month before that, I described the effort to create a new program called Chandler. This month’s tech-literature pick, Dreaming in Code, by Scott Rosenberg, is the full chronicle of that effort. The book is the first true successor to Tracy Kidder’s Soul of a New Machine, and is written with a combination of technical sophistication and narrative skill not seen in many years. Read it to understand what all these software wizards actually do. —J.F.

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