ActiveLock is an open-source copy protection, software licensing framework for all development enviroments supporting COM+ architecture. Core DLL available in VB2008 and VB6. Samples in C++, C#, Excel/Access VBA and keygens in PHP, ASP.NET available.
WebStats dotNet generates website statistics and analytics from IIS http log files. Best of all, it's all free and licensed under the LGPL. Gui is webbased written in C# using ASP.NET. The core of the software is designed in C# as a class library.
ManagedFusion was built on the idea of having a single Web-Portal Core, that handles modules, security, themeing, and localization. A CMS, ERP, or CRM can be easily created with this powerful framework. Mono and .Net are supported.