this depends. If the site has a high page rank, but has many outward links, and doesn't have content similar to the page in question, not much, you would be better off getting a link from a site with similar content and less of a page rank without as many outward links. BUT.... if the content is similar and it doesn't have many outward links... IT COULD BE HUGE....depending on many factors, and where your page rank is now, it could possibly bump you up anywhere from 0-3 more page rank then without the link, I would say, wihtout thinking about it too much