I just submitted by entry for the Digg API contest. Building on my earlier DiggGraphr tool, I was fairly easily able to port it to Apollo. I even added some customization features, like refresh interval and stuff. For more details on the application, check out the application page here. Feedback is always welcome 🙂
PS, it took me a while understanding some file metaphors that apollo has. So this is just the first version of the application. Hopefully, I will add more features to it soon :).