It turns out there are many that are interesting and offer a) some immediate use in my current projects or b) a learning opportunity to see how something has been implemented.

The problem is that the search on code.google.com sucks and there is no way to filter by date / activity / lastUpdatedDate etc.

So, the only way you are going to discover new projects is by clicking through every single page until you find something interesting and very few have time for that.

I am thinking it might be an interesting project to write a crawler that would periodically crawl the site and publish notifications about new projects to subscribers who can opt-in to notifications about a particular label (gwt/jquery/appengine etc.).

Would you find this useful? Are there other ways of doing this today?