As many other user of the slingbox, I have been able to connect my ROKU box with it. I have use some audio splitters to send both audio from my cable box and roku box. This splitter are (Y) type so they can be connected independly from each other. I dump the stereo sound to make the left audio feed to my cable box and the right audio feed to my roku box. You can select either one if you have the sling software installed in your PC. It works great, if you want to stream this content to your mobile phone like the Android. There is not app for Netflix yet and there is only an app for Hulu PLUS available only for iPhone users. It kind of sucks he. Well, this might be the solution then. I have made a small video about this so you guys.
This might be the solution for those slingbox users like me who wants more than cable on our android smart phone