Google is bringing Related Links back, but in limited fashion. You can demo the tool, but if you want complete access, you need to request an invitation to the Labs version by sending an email to email@example.com.
What Related Links does is find similar links to a URL that you enter. I demo-ed the tool using my last blog post, about new Google AdWords templates.
Here's what happened.
I wouldn't say the list of related links is the best. You could do a search in Google for "site:http://blog.searchenginewatch.com display ad builder" and come up with better results. But I guess that's why it's in Labs. It will be interesting to see if it improves.