It looks that they've just released a new major version of CppDepend - great static code analysis tool for C++. What's New in CppDepend 4 page lists several improvements. What is more important though is that they've decided to give away Pro license for free to open source C/C++ contributors. They say:
To apply for this free license, Please make sure that you meet the following criteria:
I think it's worth trying to apply for that. See also my review of CppDepend.