kexec is a means to shutdown a running Linux kernel and replace it with a different executable such as are new Linux kernel or a bare metal .dol program. It is clearly different from the other loaders listed above in that it requires you to already have booted a Linux kernel before it can be used. It is however very useful to speed development of new kernel features as it is much more agile then loaders such as ViperGC or MAX Drive Pro which take some effort to reprogram.
If your distro does not come with kexec, perform the following:
wget http://gc-linux.org/down/isobel/kexec/kexec-1.101.bin mv kexec-1.101.bin /sbin/kexec chmod a+x /sbin/kexec
Now, you must edit you reboot script - generally /etc/init.d/reboot
Search for the line "reboot -d -f -i" and add "/sbin/kexec -e -x" immediately before it.
Now it is possible to simply run "kexec [myDol].dol"!