Pandora

If you spend a lot of time at your computer (or stream music from your computer), you should know about Pandora. This Web site lets you create your own "radio stations" to match your musical tastes. For example, if you create a station called "Miles Davis Radio," you'll hear music by Davis, Max Roach, Coleman Hawkins, Lee Morgan, and other cool/hard bop stuff. Create "Britney Spears Radio" (which I just did, out of morbid curiosity) and you'll get Britney, TLC, Nelly Furtado...wait, this might actually be kind of fun at dinner parties. You can skip songs you don't want to hear, buy those you like from iTunes or Amazon through direct links to those sites, and further customize your stations with thumbs up/thumbs down "guide us" buttons.

All good, and today it got better with the addition of classical music (an egregious omission from the start).

Pandora is free. For a time, they were seeking subscribers, but they don't seem to do this anymore. Their advertisers include Budweiser, Virgin Megastores, and American Express, so maybe they don't need to.