Yes, I have just successfully installed the SuSE Linux 10.0 on my OldWorld PowerMac 7300 (PPC G3/300Mhz, RAM 272Mb, SCSI HDD 6GB, SCSI CD-ROM). It works just fine. One problem is that it can use only 16-bit graphics on the display, which looks ugly (seems like video card is too old for this OS). But this problem is minor, since I'm going to put this machine on network and use it remotely only, i.e. through telnet and command line interface.