I'm using quite a few of the Google services to push the content of my site: http://villagefilm.googlepages.com

The site is essentially an "open-source" community-built film project, using Google-provided tools to tackle each step: from scriptwriting to storyboards to auditions and eventually even the final release of the film!

I'm not really using any APIs or CSEs (yet), but I do use a wide range of Google services to accomplish my goals. And it's fun!

Your site rocks, by the way. I've been subscribed to your feed for a while, but haven't commented for some reason or another. Anyhow, you're always one of my first clicks in Reader.