Columbia University's Digital Scriptorium is a database of high quality scans from medieval and renaissance manuscripts. The highlights section alone is breathtaking, but you can search and browse through over 5000 manuscripts and almost 25000 individual images.
posted on May 3, 2008 - View this thread

A few examples of high-quality re-creations of medieval armor. Much of this is created using historical techniques (youtube,) by men (slightly NSFW) who can only be called masters. But it ain't cheap.
posted on Dec 7, 2007 - View this thread

Medieval & Renaissance Manuscript Images: Corsair is a well documented online image repository of the Morgan Pierpont Library. There are 58 manuscripts with over 7,000 images ranging from the 9th to the 16th century. Sample image page. Sample search results. Research information.
posted on Sep 3, 2005 - View this thread

Gode Cookery: Medieval & Renaissance food & cookery, and more.
posted on May 7, 2004 - View this thread

Musica Antiqua: A Guide to Medieval and Renaissance Instruments. Complete with both .wav and .mp3 samples.
posted on Mar 12, 2004 - View this thread