Can you break down where/how the bandwidth is used to a device? Does everything that goes to a chumby get proxied through chumby servers?
No - most of the data loaded into a widget (like photos, video, most data) comes directly from the third party service.
Chumby *does* provide a couple of services that are used to implement some widgets. For instance, we do proxy the access to data *about* SHOUTcast streams, since you require an developer-assigned API key to get that data. We take the request from the device, add the key, and forward the request to SHOUTcast , then pass the response back to the device. the audio stream itself comes directly from the stream provider. In this, and a few other services, we're required to keep the API key secret. When the device makes a request to us, we verify that the device is legitimate to prevent others from leeching on the service - again, this is generally required by the contract with the third party.
There are similar systems in place for iheartradio, Pandora, Photobucket, eBay, Flickr, Instagram, and a few others. Again, this is mainly for authorization and metadata - the big data comes directly form the provider. In a few of them, we also enforce regional restrictions, per the contract.