First let me tell you what happened...

I was messing with ddwrt and overclocked it to 300mhz (just playing around) and it bricked (flashing power light).  I was able to do the 30/30/30 to get it back and I overclocked it again, working my way up to 28x before it bricked again.  This time the 30/30/30 trick would not work.  I tried shorting the pins on the flash and that wouldn't work.  At this point I had this...
1. flashing power light
2. no dmz light
3. ping failure
4. web gui failure

I used a JTAG cable and flashed and then using TFTP uploaded the original Linksys firmware (using Knoppix) and even ddwrt-mini.

Now ping works but no web gui.   I still have blinking power light and now the dmz light is blinking (4 sec on/4 sec off).  It seems everything I try acts like it is working but I can't get the web gui or telnet to work.

Any suggestions, I'm going to try Openwrt and Tomato tonight...

What is this 30/30/30 and where can I find the information about?

I was refering to the technique of...
power up
hold reset down for 30 secs
pull power plug (while still holding reset) and wait for 30 secs
power up (while still holding reset) and wait for 30 seconds
release reset button

Thanks for your explanation/clarification.

Ok, I've made some progress (I think).

Power LED = on (not blinking)
DMZ LED = Off
WLAN LED = on

Serial console works and get root@OpenWrt:/#
Can't ping 192.168.1.1 (timeout)
web interface doesn't work (timeout)
tftp doesn't work (timeout)

Any ideas?

Have you tried shorting pins 15 and 16 on the flash memory chip? I've successfully debricked my routers every time with this method.

Pin shorting is VERY bad only use that as a last resort, what router model is that, if memory serves me, with the linksys wrt54g(s) 1-4 if you get a ttl of 100 for the pings you are talking to the CFE not whatever firmware image you uploaded.  If you can get the model number someone may be able to help you more.