Finding Open Source Android applications

I love my HTC Hero and growing number of applications that are available for it. However the marketplace really doesn't make clear the difference between free (as in beer) and free (as in freedom). For all sorts of reasons I'd like to be sure the code running on my new favourite device is Open Source. I've been scratching my head about the best way to find a decent applications and had been throwing all sorts of queries at Google and generally getting lost in a sea of links. A lot were irrelevant as proprietary apps get mentioned on news sites with Open Source sections.

Then I had a slight brainwave (you wondered what the burning smell was?). Seeing as the most important thing is having available source code I skipped the main Google index and used their excellent code search. As every Android application contains an XML file called "AndroidManifest.xml" every thing else is a process of refinement.