Anyboard.io

https://anyboard.io/#custom

I don't know enough to say for sure, but it seems like this product, available free on AppleTV, is not too many steps away from being able to be integrated with Indigo. It uses a JSON scheme to configure the data you want to display, and appears well documented.

The configuration itself is slightly less so though, as I can't tell if you can just use their AppleTV app pointing to a local server hosting the schema and the data, but it sure seems that way!