In Drupal 7, how can I include a CSS file only when the front page is being viewed?

Question

I'd like to include a particular CSS file only when the front page is being viewed, since it only applies to the front page, and it's a relatively large file. I know that the solution will involve using drupal_add_css(), but I'm not sure where in my theme's template.php file this would go. Is there a particular hook within my theme that I should be implementing to use this? Thanks.

EDIT: I essentially have the code down, I'm just not sure what hook is available to my theme files to implement. The actual code will look something like...

if (!strlen(request_path())) {
    drupal_add_css(drupal_get_path('theme','mytheme'). '/css/front.css');
}

Answer 1

Try this:

function mytheme_preprocess_page (&$variables)
{
  if (drupal_is_front_page()) {
    drupal_add_css(drupal_get_path('theme','mytheme'). '/css/front.css');
  } 
}

See template_preprocess_page and drupal_is_front_page for more info.

Answer 2

The CSS Injector module allows you to do just that.