I see the box when I publish something where I can add more URL's to ping. I also see that two URLs are automatically pinged whenever I publish something.

What do others put into this box?
Do people that I ping need to know me, or can I ping strangers? Would I want to?
Is there a list of good URL's to ping somewhere?


Thanks
Mathias

I believe the URLs to ping box on the Edit Entry screen is specifically intended for Trackback URLs - so if you see a post on another blog which is Trackback-enabled, this box permits you to ping that other blog's entry.