One of the tricky things about building Web content is navigation so here at the Network World Web Applications newsletter we're always on the lookout for new tools to make site organization easier to understand.One of the favorite methods used to show site structure is the tree. At its simplest, a tree is a static indented list that shows the hierarchy of content to some arbitrary level of granularity.At its slickest, a tree menu is dynamic allowing for variable content such as the current files in a subdirectory and folding - the hiding of the subtree below a specific tree node.The trick with the static menus is to produce good looking layouts while the problem with the dynamic features is that they are complex to code requiring either an applet or Dynamic HTML support. And for dynamic features making a tree menu system operate cross-platform adds an order of complexity to the coding.So I was pretty excited to find iNavigate Menu from Cirkadia (see links below). INavigate is a DHTML implementation that is created by the iNavigate Tree Menu Generator.The iNavigate Generator allows you to design a menu hierarchy using drag and drop to specify captions, URLs, Tool Tip help, hover text and subtree grouping. You can save your menu hierarchy in XML and replicate it across your Web pages.The Professional Gold edition includes a DLL that allows you to generate menus dynamically from code, which means that dynamic hierarchies can be created on the fly from live content and data. You can also dynamically modify the XML specification files from other Web applications.Lest you have any doubts about the sophistication of this system, iNavigate features includes:* Unlimited menus nodes and nested levels.* Menus that stay open or closed as you navigate through the site (session cookies are used to store the menu state and automatically restore them on the next page).* Custom tree-style graphics and tree library with the Professional versions.* Menus that automatically follow as the user navigates through your site using links on the page.* Support for links or buttons that open or close all menus, plus move next or move previous with a single click.* Graceful functional degradation for browsers that don't support iNavigate.* Support for sub-pages below a page on the menu structure.* Multiple entry points so that visitors can enter a Web site on any page and iNavigate will display the correct menu item.* Search engine compatibility.* No dependency on frames as well as an explicit frames mode.* Keeps graphics correctly aligned for dynamic text font and size alteration.INavigate comes in several editions: iNavigate Personal ($49) to create basic iNavigate menus; iNavigate Professional ($149), which provides all complex menu designs, extensive customization and server application integration; and iNavigate Professional Gold ($349), which extends your use of the Professional edition on any number of domains or servers.There's also a Free Menu Code Edition that features instructions on how to build an iNavigate menu by hand and includes an evaluation version of the iNavigate Generator.From my brief look at this product it is really impressive. On PCs it runs under Internet Explorer 4.0+, Netscape 6.0+, Mozilla 0.6+\u00a0and other Gecko-powered browsers, Opera 7.0+, Opera 5.12+ [Partial Active Mode, inline with browser capabilities], and Camino (formerly Chimera) 0.5+. On the Macintosh it runs under Internet Explorer 5.1+ on OS X, Netscape 6.1+ on OS X, Internet Explorer 4.5 and 5.0+ on Classic Mac, and Netscape 6.0+ on Classic Mac. iNavigate supports Passive Mode on all other non-supported browsers, versions, or platforms.