Open soruce the BizTalk core engine source code
Following the Visual Studio and .NET pattern, the BizTalk's core engine source could be open sourced/shared. This could also community to extend or trouble shoot the core engine.
Commercial interest could be protected by have some with some agreement terms.
There is plans for make more features from BizTalk available through Open Source projects, stay tuned!
Andrej Medic commented
Open source the BizTalk Server Business Rule Engine...