- ARM Linux
A Linux distribution for Acorn systems. Based on Red Hat.
- ELKS - The Embeddable Linux Kernel Subset
A variant of Linux for 8086 and 80286 class PCs. :-)
A Linux distribution for Power Macs (supported by Apple). It is based on a variant of the Linux kernel which uses the Mach microkernel.
Another Linux distribution for PowerMac and PReP machines - based on the regular monolithic Linux kernel from Linus. RPM based.
- Linux/m68k (not really a distribution)
There is much work being done to get the Linux kernel to work on Motorola m68k-based systems, such as the old Macs, Amigas, Ataris, MVME boards, old HP 9000/300 workstations, black NeXT hardware, and Sun 3 workstations.
The Debian project is putting together an m68k distribution. And there is a collection of m68k RPMs on ftp.redhat.com/pub/m68k/. In addition, there is the German
Eagle Linux M68k distribution for Amiga machines.
A Linux distribution for Silicon Graphics MIPS-based machines. Red Hat based.
A Linux distribution for Sun UltraSPARC machines. Based on Red Hat.
- Extreme Linux
A Linux distribution for Beowulf class machines (many machines tied together via networking that act as a single supercomputer). Based on Red Hat.
- Guardian Networks Secure Linux
A specialized Linux distribution with a modified "hardened" Linux kernel and other security enhancements.