I recently picked up an Onkyo TX-NR708 receiver since my 12 year old JVC couldn't decode DTS-HD audio from Blu-ray discs. As I was reading through the stack of docs that came with it, I came across a packet that was the GPL license information along with a list of packages used. Turns out the thing runs Linux + busybox. It also has a web server. Makes sense I suppose, as it does streaming of various internet and local audio.
On the topic of the actual receiver, I have been quite pleased with it. It was easy to set up and certainly reduced the clutter in my AV stack. Now I just need to decide which video streaming device to pick up.
--SS