Originally posted here by h3r3tic
Get a firewall that drops pings or doesn't respond to them, then they won't know if you're there or not. It's kinda security by obscurity, unless you actually configure the firewall correctly, then it's good. I don't know how to edit the response though.
That is what I do.
I allow it internal on my LAN/WAN but deny it from the internet.

Not to hijack your thread, but is there any real reason to allow replies?
(other than troubleshooting connectivity)

I drop ICMP but send keepalives to my ISP so they don't release/renew my public dynamic IP until I request it.

There are lots of sites/people now dropping ICMP (including AO) and they all still function fine.