Melody Tubes is a great way to find and listen to some of your favorite song files. At the top of the page is a search bar. First, type in text from song lyrics, the name of a song or an artist, or even text from a mix, and then search. Melody Tubes will return everything it can find that fits your criteria, sorted in order of relevance, just like with any standard search engine. These search results will appear with down the right-hand sidebar with thumbnail images and two options for you to click. The first option, play, loads a video in the center of the page, powered by youtube, of the song you've selected. The second option, view lyrics, loads the lyrics of the song without starting the video, displaying them in the description area underneath the video window in the center. Finally, above both of these options, there will be a "plus sign" icon, which brings us to one of the best features of this engine.
Clicking on this adds the video to a playlist. Your playlist, which will update as you change it, will be displayed along the bottom of the page, and can be edited fully. Videos can be deleted or moved around, and once you've created a playlist you like, it can be saved and loaded at any time later.
Overall, Melody Tubes is a good, albeit basic search engine for music files, but because it's powered exclusively by youtube, your results are limited to what's available there. Sometimes what you're looking for may not be on youtube at all, or the video that is there might not be very good quality, and sometimes, with uploads being deleted from youtube or embedding being disabled on a video, things that you may have been able to find and add to a favorite playlist in the past might go missing later on, but if what you're looking for is music videos, this is still a great way to find them.