Browser button add-on that eliminates superfluous items from YouTube (ads, comments). Just install in the browser bookmark toolbar, browse to the desired video, and click the Quietube button.
"Noteflight® is an online music writing application that lets you create, view, print and hear music notation with professional quality, right in your web browser. Work on a score from any computer on the Internet, share it with other users, and embed it in your own pages. Noteflight is free for individual use. "