Show a random post from a category, excluding the current post

gistfile1.aw

<?php // show a random video from the last 10 posts in the video category 

  $vidCount = rand(0, 9); 

  $my_query = new WP_Query( 
    array(
      "cat" => 11, 
      "showposts" => 1, 
      "offset" => $vidCount, 
      "post__not_in" => array($post->ID) // exclude the current post from the list
    )
  );

  while ($my_query->have_posts()) : $my_query->the_post(); 

    // get the medium version of the thumbnail image (i.e. 300x200)
    $src = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'medium' ); 
  ?>

  <?php if ( has_post_thumbnail() ) { ?>
    <a href="<?php the_permalink() ?>">
      <img src="<?php echo $src[0]; ?>" alt="<?php the_title(); ?>" title="<?php the_title(); ?>" />
    </a>
  <?php } ?>

<?php endwhile; ?>