I couldn't find another thread on this, but last year in Munich a treasure trove of "Lost Art" was discovered. Many, many lost treasures. The authorities have been investigating the various pieces of artwork, and is hoping to return some pieces to their rightful owners. To that end, they've established a fascinating website, that shows many of the pieces. I hope that many of the pieces end up being publicly displayed.
Lost Art Internet Database - Munich Art Trove