I once spent a memorable Shabbos at the home of Rabbi Dr. Shnayer Leiman. His library is legendary, and some of the treasures of the collection are now featured on the website http://www.leimanlibrary.com. An especially valuable resource on this website is a collection of over a hundred articles by Rabbi Dr. Leiman that can be freely downloaded, including such treats as The Adventure of the Maharal of Prague in London. It's a real treasure trove!

(Thanks to S. for letting me know.)