Error Handling, Apache and PHP.
Error Handling, Apache and PHP
I'm on record as using this for my sites so here's a good tutorial that I can endorse fully:
Using PHP and Apache, you can turn your “Page Not Found” messages into more than bland error reports. You can serve an alternate page based on the name of the page that was not found, create a page on the fly from a database, or send an email about the missing page to a webmaster. [_Go_]
How else do you think you got this beautiful picture? True there are a lot more things I could have done with it (which are covered in this tutorial).