A sort of follow up/related question to this.
I\'m trying to get a grip on a large code base that has hundreds and hundreds of classes and a large inheritance hierarchy.
For a reasonably priced commercial product, you may want to check out SolidSX from Vizlogix (www.vizlogix.com). (If you are outside of North America, go to SolidSource -- www.solidsourceit.com.)
It generates a radial diagram that can be collapsed and expanded. It also integrates with Visual Studio (both BSC and .NET).