For music lovers, hooktheory.com lifts the lid on what makes good songs.
Hooktheory.com is a beta version of a site that breaks down and analyses thousands (maybe millions) of songs and finds patterns in the chord progressions in those songs. With this information, the budding song writer can structure a proven chord progression based on other popular progressions. You can also experiment with patterns using the Trends tool. Start with a chord and it will then show you popular progressions from there as well as songs that share the same progression. You can also use the editor to compose your own songs or take on the ear training challenge. There is also a book to take you through music theory and K-12 educational resources. There is even an app for the ipad to take Hooktheory with you.
Hooktheory.com is an excellent tool for exploring music and is my pick for the website of the week.