eWeek reports on an internal Apple project named "Marklar":
According to sources, the Cupertino, Calif., Mac maker has been working steadily on maintaining current, PC-compatible builds of its Unix-based OS.
The article discusses this as a fall-back plan, should the PowerPC fail to deliver... however, does not expect Marklar to become significant in the near future. An Apple-IBM collaboration is again raised with upcoming Power4-based chips.
This is not the first time Apple has looked to an x86 port of Mac OS. Project "Star Trek" accomplished the same with an older version of Mac OS.