I have used Tipfy for a couple of projects. It is VERY lightweight and flexible, and comes with jinja2 templating built in. Basically webapp + some missing comp

I have used Tipfy for a couple of projects. It is VERY lightweight and flexible, and comes with jinja2 templating built in. Basically webapp + some missing components, like Session management. It's not even as close to as robust as Django-nonrel for GAE but depending on the scope of your project it might be perfect