MorphOS has released version 2.5 of its PPC computer only operating system for older non Intel cpu Mac’s.
MorphOS includes a web browser and TCP/IP stack and a few traditional baseline OS-associated apps among its features. Further software is available from a range of online repositories. MorphOS 2.5 comes on a bootable 30-minute demo live CD ISO which may also be installed. The ISO is available for free download by anyone. The 30-minute limit is removed by online purchase of registration/key file which is available for a limited period for the sum of 111 euros to celebrate the launch of this version.
http://www.morphos-team.net/releasenotes-2.5.html