Ti.Calc is a project mainly written in C++ and C, it's free.
An example (trivial) module for Titanium Desktop - currently only meant to work with Win32 version of Titanium Desktop
This is an example module for Titanium Desktop.
To build it, you first need to get a copy of the Titanium Desktop source code. I followed these instructions for doing that (and building it):
Next,
Then run scons as usual...
scons debug=1 sdkinstaller run=1