I dont have Dish so I can not confirm this works 100% but this is a report from SlaughterX from CAG
Dish Network is giving away free Roku streaming devices. If you have Dish Network and want one then call 1-888-796-5589, then complain about not having AMC and not being able to watch Breaking Bad or Hell on Wheels. If they ask if you have a internet say yes, then if they ask if you have a device like a PS3 or Xbox say no and they will send you a Roku. Better than the $35 credit I got for Breaking Bad!