Jennifer Zaino
SemanticWeb.com Contributor

This summer the IEEE (Institute of Electrical and Electronics Engineers)published an article entitled "Exploiting Linked Data to Build Web Applications." That led us at Semanticweb.com to ponder, as the web of linked data grows, what are people doing with it? Here are some things we found out:

MusicBore

You know when you catch the end of a song on the radio station and just can't remember its title, who is singing it, or how old you were when it came out? Well, if you were listening to the song courtesy of MusicBore, you wouldn't have to ponder any of those questions -- in fact, it will tell you the answers even if you don't have any questions.

Created by researchers and software engineers affiliated with the BBC, Music Hackday in London, the automated radio DJ might put you to sleep even without playing any lullabyes. To view the app with the tongue-in-cheek name go here http://musichackday.org/hacks.php?page=MusicBore.

In addition to getting the facts about the artist and song -- and some opinions on quality -- the MusicBore mines connections that could take you down the road from the musician to the genre he or she specializes in to the definition of that genre, its major stars, and so on. Appropriately enough, it does it all in a computer-generated monotone.

Paggr

Paggr is an application that lets users create ad-hoc mashups from structured data on the web, enabling the results to combine linked data with semantic agents and personalized dashboards. Its first use case came about at the European Semantic Web 2009 conference, in the form of an ESW conference explorer system that used a few dozen RDF stores for public and user-specified dashboards.

Created by Benjamin Nowack, Paggr's developer, it used machine-readable data from the DERI (Digital Enterprise Research Institute) semantic web dog food server and created widgetsm driven by SPARQL queries, related to conference sessions, papers, people, and so on. Each link is a hyperlink to human-readable data and a linked open data identifier to interact with widgits.

The screencast demonstration at http://bnode.org/blog/2009/06/04/eswc-2009-linked-data-dashboards can get you pretty excited about where developers can take mash-ups with Paggr. Clicking on a link opens the door to interaction -- for example, users can click on a topic URI, drag it to the people widgit, and find the conference speakers and attendees who are experts in that topic. The creators expect to move the system to a DERI server.

Revyu

The winner of the 2007 Semantic Web Challenge is a reviewing and rating web site that exploits links to external sources such as DBpedia to create what it calls human-oriented mashups at the HTML level. It consumes linked data as well as exposes reviews as linked data using standards such as RDF and SPARQL. In doing so, its creators say they aimed to help create an ecosystem of interlinked reviews and ratings on the web, and to bootstrap the semantic web as a whole.

Marbles

A linked data browser for navigating across these data sets, the server-side application was released this summer on SourceForge. The browser retrieves data from multiple sources and integrates it into a single graph persistent across user sessions. It offers a full details view that lists all known properties for resources, and lets users generate Fresnel-based views, where colored dots -- aka, the marbles -- correlate the origin of displayed data with a list of data sources.

It's used by the DBpedia Mobile client, itself utilizing DBpedia linked data to provide localized data about nearby attractions on mobile phones, to give views and background information on attractions, restaurants, reviews and so on drawn from linked data sets. A public server is listed as being available at http://www5.wiwiss.fu-berlin.de/marbles/.

RKBExplorer

A user interface to a world of Linked Data, the tool is designed to help scientists developing systems that require exceptional resilience by identifying indirect but potentially significant inter-relationships between people, publications, and projects. The application at www.rkbexplorer.com presents a unified view of the resources, without directly exposing users to Linked Data or Semantic Web technologies.