"What does RECAP do?
RECAP is an extension (or “add on”) for the Firefox web browser that improves the PACER experience while helping PACER users build a free and open repository of public court records. RECAP users automatically donate the documents they purchase from PACER into a public repository hosted by the Internet Archive. And RECAP saves users money by alerting them when a document they are searching for is already available from this repository. RECAP also makes other enhancements to the PACER experience, including more user-friendly file names."
Actually, PlainSite depends upon RECAP, and I think it's a great product, which is why I mentioned the Princeton team. The essay was about PACER's pricing scheme, not about RECAP, but I fully encourage everyone to use it.