Looking for a online live tv video streaming box. HD would be a plus!

I am looking for a good STB to play live internet channels onto my HDTV, I wouldn't mind if its not HD as most of the channels i would watch wouldn't be so either. Is there such a box?
I have looked at the ROKU and the VuNow/Netflix, none of them mention being able to ad your own live tv channels from the internet.
I want to be able to ad like whichever online video streaming link onto it. I wouldn't mind if it had option to play HD video's of hdd, and other features. Mainly i want to be able to play live internet TV and be able to ad my own channels in there. Not just preset like VuNow.