Step 1:

add_action( init, videogames, 0 );
function videogames() {
	register_taxonomy( xbox360, post, array( hierarchical => false, label => Xbox 360, query_var => true, rewrite => true ) );
	register_taxonomy( playstation3, post, array( hierarchical => false, label => PlayStation 3, query_var => true, rewrite => true ) );
	register_taxonomy( wii, post, array( hierarchical => false, label => Wii, query_var => true, rewrite => true ) );
}

Step 2:

<?php echo get_the_term_list( $post->ID, xbox360, Xbox 360 games: , , ,  ); ?>

Step 3:

<?php wp_tag_cloud( array( taxonomy => xbox360, number => 25 ) ); ?>

Step 4:

<?php query_posts( array( xbox360 => the-super-game, showposts => 25 ) ); ?>