I'm evidently a little late to the party with this, but the following clip, featuring Susan Boyle from the British version of American Idol, has become an internet sensation:
(Sorry, couldn't reproduce it in blue, you'll have to type it in.) It's really quite inspirational. The most satisfying part, of course, is getting to watch the show's hosts have to live down their initial snippiness; they almost make up for it at the end with their graciousness and effusiveness at the end. Almost, but not quite.
It brings to mind a correlation I've long noticed: the best female singers tend to be the worst-looking (think Janis Joplin, or Aretha Franklin). They get promoted for their incredible voices despite their appearance. The over-hyped, under-talented ones tend to be sexier (think Madonna, or Diana Ross, who couldn't sing nearly as well as fellow Supreme Florence Ballard). Perhaps the best examples are the two women from the Mamas and Papas: 300 pound Cass Elliott had a beautifully mellifluous and seductive voice, while Michelle Phillips' weak voice relegated her to a primarily ornamental role.
There are exceptions. Joan Baez when young had a luminous beauty as well as exceptional voice. Whitney Houston, in her pre-crack phase, was a beauty. And I always thought Olivia Newton John an underrated singer. But as a general rule, there is an inverse relationship between a singer's voice and her looks.
Don't ever buy an album because you're attracted to the woman on the cover.
If, on the other hand, the woman on the cover is plain, you can be pretty sure there's great music inside.