PHP Filtering some html...

[Borgs8472]

Hi all. Not strictly a vb or even PHP question this, but I'm looking for some pointers to somewhere more appropriate if needs be.

Would it be possible to make a script that you give a parameter of an external webpage, it filters it somehow and then renders it?

I'm looking to make a custom script to rip out some adverts and and side bar from a webpage (no, it's not any vbulletin page, don't worry ).

It would basically read the webpage's html like a string, snip any content between the code I'll identify as 'ad code begins' and 'ad code ends' and then render the page.

Possibly I'd like to replace the content, but one step at a time.

I was inspired to this idea by pages such as http://www.pornolize.com/ , who seem to process webpages with finds and replaces without much apparent difficulty, though I don't know what sort of scripts they're running.

Could anyone point me in the right direction?