LinuxMCE (Score 0, Redundant)

Take a look at LinuxMCE- has MythTV and Asterisk built in... with a lot more that can be added with a little coding- e.g. Hulu support hopefully will be released in the next couple weeks. The current build (in beta still) is based on Kubuntu 8.10 and the next release is scheduled shortly after 10.04 is released next spring.