add_filter( 'post_thumbnail_html', 'remove_width_attribute', 10 );
add_filter( 'image_send_to_editor', 'remove_width_attribute', 10 );

function remove_width_attribute( $html ) {
   $html = preg_replace( '/(width|height)="\d*"\s/', "", $html );
   return $html;
}

Thanks to Damien for the cool hack!

<?php
   if (is_plugin_active('plugin-directory/plugin-file.php')) {
      // the plugin is active
   }
?>

Thanks to Cats Who Code for the cool tip!

// set arguments for get_posts()
$args = array(
    'numberposts' => 1,
    'orderby' => 'rand'
);

// get a random post from the database
$my_random_post = get_posts ( $args );

// process the database request through a foreach loop
foreach ( $my_random_post as $post ) {
  // redirect the user to the random post
  wp_redirect ( get_permalink ( $post->ID ) );
  exit;
}

Once done, upload the page-random.php file to your theme directory. Then, login to your WordPress dashboard and create a new page, called "random" (You have to call it random, otherwise, the standard page layout will apply, see WP Codex for more details about page hierarchy).

After you published the random page, any user who'll visit the http://www.yourwebsite.com/random page will be automatically redirected to a random post.

By the way, I just created a Facebook page for my websites (This include WPRecipes as well as CatsWhoCode) so don't hesitate to "like" it!

Thanks to Smashing Magazine for the cool tip!

remove_action( 'load-update-core.php', 'wp_update_plugins' );
add_filter( 'pre_site_transient_update_plugins', create_function( '$a', "return null;" ) );

Thanks to WP Snippets for the useful tip!

add_filter('gettext',  'change_post_to_article');
add_filter('ngettext',  'change_post_to_article');

function change_post_to_article($translated) {
     $translated = str_ireplace('Post',  'Article',  $translated);
     return $translated;
}

Thanks to Smashing Magazine for the cool tip!

global $wp_query;
$total = $wp_query->max_num_pages;
// only bother with the rest if we have more than 1 page!
if ( $total > 1 )  {
     // get the current page
     if ( !$current_page = get_query_var('paged') )
          $current_page = 1;
     // structure of "format" depends on whether we're using pretty permalinks
     $format = empty( get_option('permalink_structure') ) ? '&page=%#%' : 'page/%#%/';
     echo paginate_links(array(
          'base' => get_pagenum_link(1) . '%_%',
          'format' => $format,
          'current' => $current_page,
          'total' => $total,
          'mid_size' => 4,
          'type' => 'list'
     ));
}

Thanks to Smashing Magazine for the cool tip!

add_filter('jpeg_quality', function($arg){return 100;});

Save the file, and you're done. That's simple as that!

Thanks to WP Snippets for the tip!

<?php
$image_id = get_post_thumbnail_id();
$image_url = wp_get_attachment_image_src($image_id);
$image_url = $image_url[0];
?>

Thanks to WP Snippets for the cool tip!

function replace_excerpt($content) {
       return str_replace('[...]',
               '... <div class="more-link"><a href="'. get_permalink() .'">Continue Reading</a></div>',
               $content
       );
}
add_filter('the_excerpt', 'replace_excerpt');

Thanks to CSS Tricks for the great snippet!

Your email is on the list? Congratulation, you won! Please email me the deal you want and I'll forward your email to the guys from Mighty Deals. They'll give you your free deal!

Thanks everyone for participating!