
Wow, I don't know why I haven't read about this anywhere (I stumbled upon it looking at the Xbox website).
Basically all you need to do is download the Zune software and then click Options, Library, Media Sharing. I just tested this using videos and it streams just fine to the Xbox (it's QUICK too!)
PS: You do not need a Zune player to install the Zune software!

the Blip Festival is a four-day celebration of over 30 international artists exploring the untapped potential of low-bit videogame consoles and home computers used as creative tools.
Familiar devices are pushed in new directions with startling results — Nintendo Entertainment Systems and Game Boys roaring with futuristic floor-stomping rhythms and fist-waving melody, art-damaged Sega hardware generating fluctuating and abstracted video patterns.
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