It was bound to happen... A very clever person has hacked the AppleTV to run OSX, turning the AppleTV box into the cheapest Mac ever (at $300 - OSX license not included!)
The hack was published by an anonymous fella who goes by the alias "Semthex" on his site www.semthex.com. "I removed a cpu check and NX usage from the original source and modified some things in memory managment* as well added a SSS3 emulation. The ATV only has a Pentium M which is not capable of SSE3. Also a issue with granularity of TSC was fixed which may lead to a divided by zero at Pentium M processors (thanks to netkas for pointing me this out)." Well, that's nice and clear then...
The fun 13-step process is not for amateurs (at least, not for amateur amateurs) and putting OSX on your AppleTV can render it useless for audio and ethernet connectivity, which sort of defeats the purpose of it being the ultimate media hub. But, we've read that other enthusiasts have being working around the clock to work around those issues.
For more info, check this site out...