Why? It would be useless to you; the effort required to write a web-based RSS client is as nothing compared to re-implementing all the internal infrastructure that Reader depends on.

If you want to run your own RSS client, starting with NewsBlur[1] or Tiny Tiny RSS[2] would get you much further than being able to see the Reader source.

[1] https://github.com/samuelclay/NewsBlur

[2] http://tt-rss.org/

What was so special about google reader that you couldn't just code yourself? It's an RSS reader, right?

http://code.google.com/p/feedparser/

I wrote a website that read RSS feeds for me years ago using that. It's really straight forward...

There are many other RSS readers out there that are open source; having the source of Google's wouldn't be much different. And the part that would be different is all the code to integrate it with Google's infrastructure, which wouldn't be particularly useful to anyone who doesn't run said infrastructure.