Lately, I have become very interested in the whole tagging/folksonomy phenomenon that seems to be a defining element of Web 2.0. In particular, I am drawn to tag clusters. While tag clouds are great for exploring the relative importance of tags in a simple manner, they don't give you any clues about the relationships among tags. Tag clusters do just that. Rashmi Sinha explains clusters here very well, so I don't have to do it.

So far, I have not seen a very good navigation interface for tag clusters. Flickr tries in vain to provide "clustery goodness," but to be quite honest, their interface is quite lame. While bread-crumb navigation works well within a site, it is bad for navigating clusters because it prevents the user from doing what comes naturally -- exploring. Instead, it forces a single-step hierarchy navigation (which works well for websites) while the user's brain is probably accelerating with the brakes on wanting to see more clusters and the relationships between them.

I think clustering calls out for a Web 2.0 version of a hyperbolic interface. Hyperbolic interfaces lend themselves very well to providing a visual representation of graphs which is basically what tag clusters are (assuming you have a starting tag). You can see this in implementations such as Thinkmap's VisualThesaurus. Unfortunately, VisualThesaurus, like Inxight, went the Java route. This makes it a complete pain to use in any kind of quick and meaningful manner. An ideal solution would be a hyperbolic U.I. that is easily implemented using either Flash or XmlHttp (Ajax). This would be more usable since most people's browsers already support it.

I Googled and came up with only one Flash instance of a pseudo-hyperbolic U.I. that I liked. It was on a marketing company's site -- Renegade Marketing. I emailed them twice about getting the Flash source, free or for a fee. Both my polite inquiries were ignored. (Tangent: Makes me wonder why companies claim to be in the marketing business when they don't even have the ability to do something as simple as acknowledge an email enquiry.). 

Does anyone know of a good, Flash-based, hyperbolic U.I.? I am creating an application that aggregates tag-based information from a variety of sites and then allows exploration of tag clusters and would like to use such a U.I. I will post more details of the application soon.