It looks like I have to sign up to use the service. I'll definitely check it out later.

Honestly, one of the biggest filters that I need is: "Show me only the papers I actually have access to. Don't show me PubMed links that don't include a full paper. Don't show me links to Elsevier journals that I look like I have access, but I really don't."

Google Scholar does usually indicate an actual, downloadable paper with a link in the margins, but it's not perfect. Sometimes I need to scroll through a few pages of results to turn up a few papers I can even access, and then they're not always relevant. Other times, there actually is a version of the paper I can access, but Google Scholar doesn't indicate that as an option, so I have to click a few times to dig deeper.