Eclipse rocks completely!
It is for something like this why Eclipse rocks so: I just love GraphViz, which has an awesome UI in its Mac OS implementation. When I saw the Windows version I was totally disappointed. Since I did some GraphViz-rendering in Eclipse before, I decided to pick up Wayne Beaton's Image Viewer from the Eclipse Evangelism site and add the rendering of GraphViz files to it. Now I have a multi-platform, open-source implementation that is on par with the best existing platform-specific solution, and it even has my favourite editor and versioning, etc. included.