I’m always looking for classical music recordings in the public domain. While there are a ton of recordings posted on various archives around the internet, I have yet to find a single authoritative place to look for free classical music online. I recently came across the music archive of the Isabella Stewart Gardner Museum in Boston. The site contains recordings of over 150 concerts performed at the museum, all free to download. You can browse by performer, composer, genre and period which is quite handy. Recordings of entire concerts are also available as a podcast which includes brief comments about the history and context of the pieces performed. The archive is far from authoritative, but it contains a growing collection of high quality recordings in a easily browsable format.