One of the key rights of an open source licence (and therefore a key property of an open source project) is the right to fork. If you think that a project has stagnated or been terminated then you have the right to pick up the pieces and take it in a direction of your own – provided that you have the time, inclination and ability (or can hire someone to do that for you). This is just not available in the closed source world.
NDoc2 died due to lack of resources (and due to the vapourware that is Sandcastle). However NDoc2005 lives on. This is only a beta version. However beta in the open source world means a lot more than beta in the closed source world – especially for a development tool.
This seems to work just fine as is. It creates MSDN style documentation from C# 2.0 source. I had it working without reading the manual in about five mins. This is in comparison to Sandcastle (the microsoft equivalent) where I have yet to generate a single file. This may get my project sufficient documentation to last until Sandcastle catches up (in a year or so).