Is there a way/tool that could show me all the classes/interfaces that implement a certain interface in my project? In Eclipse (Java) I would use the context menu "Open Type Hierarchy" option, which would show me a (pretty) tree of types that extend the selected type. Is there a tool to do the same in .NET?
I second Marc's recommendation of .NET Reflector - and would like to add that there is an impressive series of add-in available at CodePlex.
Just a few of the add-ins I use with regularity: