List active taxonomy terms

Well I did it..

        <ul id="filter">
                <li><a href="#" class="current" data-filter="*" title="">*</a></li>
                <?php $term = get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' ) ); ?>
                <?php
                $term_id = $term->term_id;
                $taxonomy_name="categories";
                $termchildren = get_term_children( $term_id, $taxonomy_name );

                foreach ( $termchildren as $child ) {
                    $term = get_term_by( 'id', $child, $taxonomy_name );
                    echo '<li><a href="#" data-filter=".' . $term->slug . '">' . $term->name . '</a></li>';
                }
                ?>

            </ul>