Favourite Open Source Google App Engine apps (Java

Question

To learn from good examples, what are the best open source Google App Engine applications out there?

I don't care if it is Java or Python based.

Please one app per answer. Feel free to add a link to the live app (if there is) and to the project page.

Answer 1

UserInfuser, a gamification platform: http://code.google.com/p/userinfuser and https://github.com/nlake44/UserInfuser

It can help you add gamification elements to your website (badges and leaderboards). It uses the Channel API for badge notifications.

Answer 2

Eezee MVC is An Easy Model, View, Controller Framework for Google App Engine.
Features

Has a Controller Class that does routing, handling and rendering templates.

Your controllers reside in the controllers folder, views (html Django templates) in views folder, models in models folder.

Allows Controller to recieve GET/POST parameters as function arguments.

Answer 3

Pubsubhubbub: A simple, open, server-to-server web-hook-based pubsub (publish/subscribe) protocol as an extension to Atom and RSS.

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

Answer 4

Rietveld of course

Answer 5

I really like FoFou which is a simple forum software that I have used.

FoFou is open source and hosted on github.

Answer 6

Khan Academy. One of App Engine's bigger customers. https://khanacademy.kilnhg.com/Repo/Website/Group/stable/Files