I friend came a couple of hours ago with a bricked WRT54G.
It isn’t so bad as it sounds. I was able to recover it in less that 15 minutes.
There is a nice howto in the openwrt site ([url]http://www.openwrt.org/OpenWrtDocs/Troubleshooting[/url]), look at the JTAG-adaptor Method. I build the adapter with one minor change. The ground is not on pin 12 of the JTAG but on the pin 10. Check it with your multimeter, before you connect it.
If you want to read the firmware it will take you about 1 hour.
A simple “[b]wrt54 -erase:nvram[/b]” did the trick for me.
Nice now we have a solution if something goes wrong 🙂