WARNING: Any device that is designed to primarily act as a "TV-connected device" has MORE RESTRICTIONS on it than a HDPC: [1] [2]

hardware solutions

Hulu Hulu Plus Netflix OTA ATSC YouTube notes
WD TV no no
Boxee no "coming soon" no
Roku no no
Apple TV no no no
Xbox 360 no no
Google TV no no
Orb TV yes yes ? SD only, no HD!

see here for more

software solutions

content offerings