For everyone who ever wished their computer would think more like they do, get ready for The Brain. Natrificial Software hopes that The Brain will forever change the way PC users navigate through file systems. The Brain is a GUI that allows users to create associations between files of many types and navigate through those files in a way that better mimics human thought. Think of it as the 21st century alternative to the age-old knowledge tree hierarchy. Instead of folders inside endless folders, The Brain lets users put files, documents, and Web pages (each one is considered a Thought) into collections (called Brains), and create almost infinite associations between different Thoughts.

Version 1.5 adds a few interesting twists to the product that go right to the heart of Web publishing and navigation. Thanks to the excellent browser integration, putting frequently traveled Web pages into a Brain is as simple as dragging a pointer from The Brain to the page on your browser. Once you've created a Brain full of associative links to important sites, the product saves time by letting users drill down to any included page without downloading unwanted intermediate pages. Even better, The Brain's "spidering" technology allows you to automatically create a brain that is an exact replica of any Website, with the number of levels of drill-down and links completely configurable by the user. (However, spidering did not work well on sites that use frames.)

Once you've created a Brain, it may be too good to keep to yourself. Natrificial lets users upload Brains to a part of its Website called the Think Tank. Other Brain users can benefit from your carefully constructed file system, and vice versa.

The Brain installed very easily, and Natrificial has created a series of RealPlayer tutorials that demonstrate the product's main features and basic use very well.

It does take some getting used to. But once we were able to create a new Brain that was more than just a series of useless links, we began to suspect that there might be an iceberg's worth of function lingering beneath this floating cube.

The default installation embeds the product into the right-hand side of the desktop, although there are several different configuration options, such as Float, and you can choose between Autohide or Always on Top to make best use of screen space. There are plenty of nice surprises built into the product, such as the ability to add notes such as a page summary or product description to any Thought, a History list, a Properties list that details any activated Thought, and the ability to search by keyword for Thoughts in any recently opened Brain. Switching between brains is extremely easy, and if you get stuck, Natrificial has done an excellent job with its online Help.

If you manage to get past the awkward beginning stage, The Brain can be a powerful personal desktop productivity tool. It runs on Windows 95, 98, or NT 4.0. The free version supports up to 100 Thoughts per Brain; full version (unlimited Thoughts) is $49.95. Natrificial Software, Santa Monica, CA, www.thebrain.com.

The Brain now lets users create navigable associative maps of Websites for fast and powerful surfing.