According to Law.com (here), an Internet respository of Founding-era documents, The Constitutional Sources Project, was utilized extensively by the Supreme Court in interpreting the Second Amendment. The project’s co-founder and executive director, Lorianne Updike, trained Justices Antonin Scalia, Stephen Breyer and Samuel Alito on navigating the site, which enabled them to click on different clauses of the Constitution and to locate other relevant documents.
Alan Gura, who argued and won the Heller case, characterized the project as “a powerful source” that helped him track down documents. Opposing counsel, Thomas Goldstein, said the project was important in the effort to “get the constitutional history right.”