Over time your opinions and tastes change. Today is the day for getting the music you don't really like or listen to anymore out of your way and make room for more.
– Delete all the music on your computer and/or MP3 player that makes you say "Meh." There is better stuff out there for you.
– Go through your CDs, records, tapes, wax cylinders, etc. and gather together all the things you don't care that much for anymore. Sell them or give them away.
A good place to turn old CDs you don't like into new ones you do is the newly launched lala.com where you'll receive as many CDs from your Want List as you send out from your Have List. It costs $1.49 each time you get a new disc, which is a better rate of trade than you'll usually find selling CDs and buying used ones.