The good folks at HackMii are working on a new project they call BootMii. BootMii provides a hook into the Wii system very early in the booting process (at boot2). Being able to execute code early in the boot process will allow homebrew developers to essentially do anything they want.
As described on HackMii, BootMii is quite robust. It is very brick resistant and will be an excellent tool for unbricking a bricked Wii that is already running BootMii. Because BootMii will run prior to the system menu, it is possible to execute code stored on an SD card even if the system menu won’t boot. So you can boot directly to the Homebrew Channel and run whatever is necessary to restore your Wii to working condition.
Of course, if you’ve bricked your Wii prior to installing BootMii, you may still be SOL. BootMii has not yet been released, but rest assured that it will be as soon as it is ready. I dare say that BootMii sounds very much like the Wii homebrew holy grail, and I’m very much looking forward to its official release. If you run Wii homebrew, I would highly recommend you install BootMii as soon as it is available. It could some day save your Wii’s life.