Running all posts through regular expressions set

[mdoliwa]

Hi,
I'd like to run regular expressions on all my forum posts. And then write a plugin which run these regexps when the new post is submited.
I'm going to exchange some words with adlinks, but wouldnt like them to look like regular underlined links, would be better if they could be the same as regular text, maybe a little different color.

Could you give me any tips how to do it, or where can I read about it?

1. Running regexps on all posts in forum database
2. How to create a plugin runnig set of regular expressions on post while it's being submited by an user ?
3. How to create links that look like regular text but have only different color (I wan't to leave regular links like they are)

Thanks for any help

cheers,
Marcin