WordPress/wp-content/themes/twentyten/functions.php

<?php

// Set the content width based on the Theme CSS
$content_width = apply_filters( 'twentyten_content_width', 640 );

// Your Changeable header business starts here
// No CSS, just IMG call
define( 'HEADER_TEXTCOLOR', '');
define( 'HEADER_IMAGE', '%s/images/header-1.jpg'); // %s is theme dir uri
define( 'HEADER_IMAGE_WIDTH', apply_filters( 'twentyten_header_image_width',  940 ) );
define( 'HEADER_IMAGE_HEIGHT', apply_filters( 'twentyten_header_image_height',  198 ) );
define( 'NO_HEADER_TEXT', true );

function twentyten_admin_header_style() {
?>
<style type="text/css">
#headimg {
	height: <?php echo HEADER_IMAGE_HEIGHT; ?>px;
	width: <?php echo HEADER_IMAGE_WIDTH; ?>px;
}
#headimg h1, #headimg #desc {
	display: none;
}
</style>
<?php
}

add_custom_image_header( '', 'twentyten_admin_header_style' );
// and thus ends the changeable header business

add_custom_background();

// This theme needs post thumbnails
add_theme_support( 'post-thumbnails' );

// We'll be using them for custom header images on posts and pages
// so we want them to be 940 pixels wide by 198 pixels tall (larger images will be auto-cropped to fit)
set_post_thumbnail_size( HEADER_IMAGE_WIDTH, HEADER_IMAGE_HEIGHT, true );

// Add default posts and comments RSS feed links to head.
automatic_feed_links();

// Make theme available for translation
// Translations can be filed in the /languages/ directory
load_theme_textdomain( 'twentyten', TEMPLATEPATH . '/languages' );

$locale = get_locale();
$locale_file = TEMPLATEPATH . "/languages/$locale.php";
if ( is_readable($locale_file) )
	require_once( $locale_file );

// Get the page number
function twentyten_get_page_number() {
	if ( get_query_var('paged') )
		echo ' | ' . __( 'Page ' , 'twentyten' ) . get_query_var('paged');
}

// Control excerpt length
function twentyten_new_excerpt_length( $length ) {
	return 40;
}
add_filter( 'excerpt_length', 'twentyten_new_excerpt_length' );


// Make a nice read more link on excerpts
function twentyten_new_excerpt_more($more) {
	return '&nbsp;&hellip; <a href="'. get_permalink() . '">' . 'Continue&nbsp;reading&nbsp;<span class="meta-nav">&rarr;</span>' . '</a>';
}
add_filter( 'excerpt_more', 'twentyten_new_excerpt_more' );


// Template for comments and pingbacks
function twentyten_list_comment( $comment, $args, $depth ) {
	$GLOBALS['comment'] = $comment; ?>
	<?php if ( '' == $comment->comment_type ) { ?>
	<li <?php comment_class(); ?> id="li-comment-<?php comment_ID(); ?>">
		<div id="comment-<?php comment_ID(); ?>">
		<div class="comment-author vcard">
			<?php echo get_avatar( $comment, 40 ); ?>
			<?php printf( __('<cite class="fn">%s</cite> <span class="says">says:</span>'), get_comment_author_link() ); ?>
		</div>
		<?php if ( $comment->comment_approved == '0' ) : ?>
			<em><?php _e( 'Your comment is awaiting moderation.', 'twentyten' ); ?></em>
			<br />
		<?php endif; ?>

		<div class="comment-meta commentmetadata"><a href="<?php echo esc_url( get_comment_link( $comment->comment_ID ) ); ?>"><?php printf(__('%1$s at %2$s'), get_comment_date(), get_comment_time()); ?></a><?php edit_comment_link(__('(Edit)', 'twentyten'),'  ',''); ?></div>

		<div class="comment-body"><?php comment_text(); ?></div>

		<div class="reply">
			<?php comment_reply_link( array_merge( $args, array('depth' => $depth, 'max_depth' => $args['max_depth'])) ); ?>
		</div>
	</div>

	<?php } else { ?>
	<li class="post pingback">
		<p><?php _e( 'Pingback: ', 'twentyten' ); ?><?php comment_author_link(); ?><?php edit_comment_link ( __('edit', 'twentyten'), '&nbsp;&nbsp;', '' ); ?></p>
	<?php }
}

// Make the Visual Editor styles match the theme's styles
function twentyten_my_editor_style( $url ) {
	if ( !empty($url) )
		$url .= ',';

	// Change the path here if using sub-directory
	$url .= trailingslashit( get_stylesheet_directory_uri() ) . 'editor-style.css';

	return $url;
}
add_filter( 'mce_css', 'twentyten_my_editor_style' );


// Remove inline styles on gallery shortcode
function twentyten_remove_gallery_css() {
	return "<div class='gallery'>";
}
add_filter( 'gallery_style', 'twentyten_remove_gallery_css' );


// For category lists on category archives: Returns other categories except the current one (redundant)
function cats_meow( $glue ) {
	$current_cat = single_cat_title( '', false );
	$separator = "\n";
	$cats = explode( $separator, get_the_category_list($separator) );
	foreach ( $cats as $i => $str ) {
		if ( strstr( $str, ">$current_cat<" ) ) {
			unset( $cats[$i] );
			break;
		}
	}
	if ( empty($cats) )
		return false;

	return trim( join( $glue, $cats ) );
} // end cats_meow


// For tag lists on tag archives: Returns other tags except the current one (redundant)
function tag_ur_it( $glue ) {
	$current_tag = single_tag_title( '', '',  false );
	$separator = "\n";
	$tags = explode( $separator, get_the_tag_list( "", "$separator", "" ) );
	foreach ( $tags as $i => $str ) {
		if ( strstr( $str, ">$current_tag<" ) ) {
			unset( $tags[$i] );
			break;
		}
	}
	if ( empty($tags) )
		return false;

	return trim( join( $glue, $tags ) );
} // end tag_ur_it

// Register widgetized areas
function twentyten_widgets_init() {
	// Area 1
	register_sidebar( array(
		'name' => 'Primary Widget Area',
		'id' => 'primary-widget-area',
		'description' => __( 'The primary widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 2
	register_sidebar( array(
		'name' => 'Secondary Widget Area',
		'id' => 'secondary-widget-area',
		'description' => __( 'The secondary widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 3
	register_sidebar( array(
		'name' => 'First Footer Widget Area',
		'id' => 'first-footer-widget-area',
		'description' => __( 'The first footer widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 4
	register_sidebar( array(
		'name' => 'Second Footer Widget Area',
		'id' => 'second-footer-widget-area',
		'description' => __( 'The second footer widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 5
	register_sidebar( array(
		'name' => 'Third Footer Widget Area',
		'id' => 'third-footer-widget-area',
		'description' => __( 'The third footer widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

	// Area 6
	register_sidebar( array(
		'name' => 'Fourth Footer Widget Area',
		'id' => 'fourth-footer-widget-area',
		'description' => __( 'The fourth footer widget area' , 'twentyten' ),
		'before_widget' => '<li id="%1$s" class="widget-container %2$s">',
		'after_widget' => "</li>",
		'before_title' => '<h3 class="widget-title">',
		'after_title' => '</h3>',
	) );

} // end theme_widgets_init

// Add all the groovy widget areas
add_action( 'init', 'twentyten_widgets_init' );