Marc or someone mentioned YouTube a few posts back. I actually have about 30 tunes on YouTube -- mostly lyric videos, At least the words change, and I don't have to worry about how many different angles I can figure out for the singer's headshots.
A couple of years ago, I decided(not for the first time) to check out Marc's website. On it were a bunch of short YouTube videos (including one on "gherming" -- outside of Nashville, I'd never heard that concept before -- but I digress). So, I watched every last one of them - 8 or 10, as I recall). Some were actually quite entertaining.
A few days later, I went and punched in my own name (obviously wanted to listen to the best music available). In the YouTube page format, to the right of the page, are "thumbnails" either of your songs, or songs you have listened to recently. Or videos you have watched lately. Underneath the thumbnail is a caption "recommended for you". They must use some fancy algorithm to pick these.
What did I see? A half dozen of Marc's YouTube videos "recommend for me"!!!! It took a few weeks for them to disappear.Some popped up for months afterwards. Talk about in your face marketing!
Here's a disaster I avoided, because I a;ready had experienced it. Did you know that if you "like" someone else's video, it will suddenly appear on the top of your own video page, supplanting your own song(s)? "Like" more than one, all of a sudden anyone looking at your YouTube page will see a whole bunch of other people's songs! I NEVER like anyone else's songs just for that reason. It's the on line version of letting someone butt in line in front of you.
Other than that,I find it a good marketing tool. Rather than an MP3,they get a lyric video where they can listen and read the lyrics while they do. So,if you're looking for excellent music, go to Ott Lukk YouTube . . . it's that easy! 
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