Cheap VIZIO VBR200W Full HD Blu-ray Player with VIZIO Internet Apps (VIA) Discount Review Shop
Very easy to setup with Comcast. With my Verizon Actiontec router it didn't initially work though - I had to disable WEP.
(not sure if I should blame the router or this box)
I've had it for a couple of months and it's been working great.
The lack of buttons on the device (when it's turned off) makes it somewhat kid-proof, which is a nice feature :)
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Cheap "VIZIO VBR200W Full HD Blu-ray Player with VIZIO Internet Apps (VIA)" Discount Review Shop