NodeXL: Network Overview, Discovery and Exploration for Excel

From the webpage:

NodeXL is a free, open-source template for Microsoft® Excel® 2007 and 2010 that makes it easy to explore network graphs. With NodeXL, you can enter a network edge list in a worksheet, click a button and see your graph, all in the familiar environment of the Excel window.

NodeXL Features

Flexible Import and ExportImport and export graphs in GraphML, Pajek, UCINet, and matrix formats.Direct Connections to Social NetworksImport social networks directly from Twitter, YouTube, Flickr and email, or use one of several available plug-ins to get networks from Facebook, Exchange and WWW hyperlinks.Zoom and ScaleZoom into areas of interest, and scale the graph’s vertices to reduce clutter.Flexible LayoutUse one of several “force-directed” algorithms to lay out the graph, or drag vertices around with the mouse. Have NodeXL move all of the graph’s smaller connected components to the bottom of the graph to focus on what’s important.Easily Adjusted AppearanceSet the color, shape, size, label, and opacity of individual vertices by filling in worksheet cells, or let NodeXL do it for you based on vertex attributes such as degree, betweenness centrality or PageRank.Dynamic FilteringInstantly hide vertices and edges using a set of sliders—hide all vertices with degree less than five, for example.Powerful Vertex GroupingGroup the graph’s vertices by common attributes, or have NodeXL analyze their connectedness and automatically group them into clusters. Make groups distinguishable using shapes and color, collapse them with a few clicks, or put each group in its own box within the graph. “Bundle” intergroup edges to make them more manageable.Graph Metric CalculationsEasily calculate degree, betweenness centrality, closeness centrality, eigenvector centrality, PageRank, clustering coefficient, graph density and more.Task AutomationPerform a set of repeated tasks with a single click.

Homepage for NodeXL, which uses Excel as the framework for display and exploration of graphs.

There is something to be said about software that ties itself to other successful software. I think that is “increased chances of success.” Don’t you?