I remain inordinately fond of the No Doubt song "Hella Good" because of its use in the second season of "Alias"-- which I am very sad I can't find a good YouTube clip for, as it was basically the most badass thing ever.

Also: this entire Avatar FST (http://gallo-de-pelea.livejournal.com/92769.html), or why I cannot listen to the Peter Gabriel song "Sky Blue" without tearing up.