Is there a script that autolinks text on any page?

Just like the title

Looking for something that will autolink on a page once it is loaded by a user.
For example I have a social network for north west Ireland, I want to link the word restaurant to my restaurant listing page.

I have only seen them coded for specific scripts, like vb.

I need something thats general because Im using it on a script and few other pages.

Thanks

 

you can change the code to replace the text with a link using regular expressions.