How To Install Apple's Front Row 1.3 on Mac OS X 10.4.8http://andrewescobar.com/frontrow
and
Turn your Mac Mini into an AppleTV
http://duggmirror.com/apple/Turn_your_Mac_...nto_an_AppleTV/
if the function is all you want you could just use the above info to turn a mac into a appleTV.
that being said i still would like to see the appleTV hacked. for the same reason people make a hackntosh a hackTV would be fun to make too.