In your ear: Listening to music via the earbuds that typically come bundled with MP3 players can be like drinking champagne out of a plastic kiddie mug. Most users seem content to put up with the buds' inadequacies, but it doesn't mean you have to.
Anyone looking to ditch their old or new earbuds needs to think about what kind of device to replace them with. Serious listeners might find that hours of wearing conventional headphones can be a trial with the constant pressure on their ears, and have an unfashionable look that made earbuds popular in the first place.
So far, the next best option is ear-canal earphones, which once fit are light and easy to wear and do a better job acoustically by blocking exterior noises.