Regular WP snippets I use.

wp-snippets-child-theme.css

/***********************************************************************************
  THEME NAME:  Parent Theme - Child
 ***********************************************************************************

  Template:    parent-theme
  Author:      Tom Blanchard
  Author URI:  http://tomblanchard.co.uk
  Version:     1.0

 **********************************************************************************/
 
@import "../parent-theme/style.css";

wp-snippets-functions.php

<?php

  /**
   * Custom images sizes, hard cropped and soft.
   */
   
  add_image_size('200-hard', 200, 200, true);
  add_image_size('200-soft', 200, 200);
  
  
  /**
   * Theme directory URIs.
   * 
   * 1. Parent theme.
   * 2. Child theme.
   */
   
  get_template_directory_uri(); /* [1] */
  get_stylesheet_directory_uri(); /* [2] */
  
  
  /**
   * Enqueue custom CSS.
   */
   
  wp_enqueue_style('custom-css', 'custom.css', array());


  /**
   * Remove size attributes from the "the_post_thumbnail()".
   */
   
  function remove_thumb_size_attribute($html) {
    $html = preg_replace('/(width|height)="\d*"\s/', "", $html);
    return $html;
  }
  add_filter('post_thumbnail_html', 'remove_thumb_size_attribute', 10);
  add_filter('image_send_to_editor', 'remove_thumb_size_attribute', 10);
  
  
  /**
   * "/?s=" to "/search/" in URLs.
   */

  function change_search_url_rewrite() {
    if (is_search() && ! empty($_GET['s'])) {
      wp_redirect(home_url("/search/") . urlencode(get_query_var('s')));
      exit();
    }
  }
  add_action('template_redirect', 'change_search_url_rewrite');
  
  
  /**
   * Truncate string with dynamic string source / character limit, usage:
   *
     echo text_truncate('Text here.', 1);
   */

  function text_truncate($text, $limit) {
    $excerpt = explode(' ', $text, $limit);
    if (count($excerpt)>=$limit) {
      array_pop($excerpt);
      $excerpt = implode(" ",$excerpt).'...';
    } else {
      $excerpt = implode(" ",$excerpt);
    }
    $excerpt = preg_replace('`[[^]]*]`','',$excerpt);
    return $excerpt;
  }

wp-snippets-loop.php

<?php if (have_posts()) : ?>

  <?php while (have_posts()) : the_post(); ?>
  
    <?php the_ID(); ?>
    <?php post_class(); ?>
    <?php the_permalink() ?>
    <?php the_title(); ?>
    <?php echo get_the_author_link(); ?>
    <?php the_title_attribute(); ?>
    <?php echo get_the_category_list(', '); ?>
    <?php echo get_the_time('Y-m-j'); ?>
    <?php echo get_the_time(get_option('date_format')); ?>
    <?php the_post_thumbnail('full', array('class' => '')); ?>
    <?php $the_post_thumbnail_url = wp_get_attachment_image_src(get_post_thumbnail_id($post->ID), 'full', false, ''); ?>
    <?php echo $the_post_thumbnail_url[0]; ?>
    <?php the_content(); ?>
    <?php the_excerpt(); ?>
    <?php echo get_the_tag_list('', ', ', ''); ?>
    <?php comments_template(); ?>
    
  <?php endwhile; ?>
 
  <?php next_posts_link('&laquo; Older Entries'); ?>
  <?php previous_posts_link('Newer Entries &raquo;'); ?>  
  
<?php else : ?>

  <p><?php _e('Oops, Not Found!', 'theme_name'); ?></p>
  <p><?php _e('Uh Oh. Something is missing. Try double checking things.', 'theme_name'); ?></p>
  
<?php endif; ?>

wp-snippets-multiple-wp-query.php

<?php
  $paged1 = isset($_GET['paged1']) ? (int) $_GET['paged1'] : 1;
  $paged2 = isset($_GET['paged2']) ? (int) $_GET['paged2'] : 1;
  $post_type_1_query = new WP_Query(
    array(
      'posts_per_page' => 1,
      'post_type' => 'post_type_1',
      'paged'  => $paged1
    )
  );
  if($post_type_1_query->have_posts()) :
?>
 
  <div>
    <?php
      while($post_type_1_query->have_posts()) :
      $post_type_1_query->the_post();
    ?>
      <div>
        <a href="<?php the_permalink(); ?>">
          <?php the_title(); ?>
        </a>
      </div>
    <?php
      endwhile;
      echo paginate_links(
        array(
          'format'   => '?paged1=%#%',
          'current'  => $paged1,
          'total'    => $post_type_1_query->max_num_pages,
          'add_args' => array('paged2' => $paged2)
        )
      );
      wp_reset_postdata();
    ?>
  </div>
 
<?php endif; ?>
 
<?php
  $post_type_2_query = new WP_Query(
    array(
      'posts_per_page' => 1,
      'post_type' => 'post_type_2',
      'paged'  => $paged2
    )
  );
  if($post_type_2_query->have_posts()) :
?>
 
  <div>
    <?php
      while($post_type_2_query->have_posts()) :
      $post_type_2_query->the_post();
    ?>
      <div>
        <a href="<?php the_permalink(); ?>">
          <?php the_title(); ?>
        </a>
      </div>
    <?php
      endwhile;
      echo paginate_links(
        array(
          'format'   => '?paged2=%#%',
          'current'  => $paged2,
          'total'    => $post_type_2_query->max_num_pages,
          'add_args' => array('paged1' => $paged1)
        )
      );
      wp_reset_postdata();
    ?>
  </div>
 
<?php endif; ?>

wp-snippets-other.php

<?php get_header(); ?>

<?php get_footer(); ?>

<?php get_sidebar(); ?>

<?php dynamic_sidebar(''); ?>

<?php language_attributes(); ?>

<?php bloginfo('name'); ?><?php wp_title('-'); ?>

<?php echo get_template_directory_uri(); ?>

<?php get_theme_mod('foo'); ?>

<?php bloginfo('pingback_url'); ?>

<?php wp_head(); ?>

<?php wp_footer(); ?>

<?php echo date('Y'); ?>

<?php echo apply_filters('the_content', $foo); ?>

<?php body_class(); ?>

<?php echo home_url(); ?>

<?php bloginfo('name'); ?>

<?php bloginfo('description'); ?>

<?php bones_main_nav(); ?>

<?php get_search_form(); ?>

<?php single_cat_title(); ?>

<?php next_posts_link(); ?>

<?php previous_posts_link(); ?>

<?php echo esc_attr(get_search_query()); ?>

wp-snippets-static-widget.php

<?php
 
  class example_widget extends WP_Widget {
 
    function example_widget() {
      parent::WP_Widget(false, $name = 'Example Widget');
    }
 
    function widget($args, $instance) {
      extract($args);
      $title = apply_filters('widget_title', $instance['title']);
      echo $before_widget;if ($title) echo $before_title . $title . $after_title;
    ?>
 
      WIDGET CONTENT HERE
 
    <?php
      echo $after_widget;
    }
 
    function update($new_instance, $old_instance) {
      $instance = $old_instance;
      $instance['title'] = strip_tags($new_instance['title']);
      return $instance;
    }
 
    function form($instance) {
      $title = esc_attr($instance['title']);
    ?>
      <p>
      <label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title:'); ?></label>
      <input class="widefat" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" type="text" value="<?php echo $title; ?>" />
      </p>
    <?php
    }
  }
  add_action('widgets_init', create_function('', 'return register_widget("example_widget");'));

wp-snippets-template-header.php

<?php
  /**
    Template Name: The name of the template
   */
 
  get_header();
?>

wp-snippets-wp-query.php

<?php
  $simple_query = new WP_Query(
    array(
      'posts_per_page' => 5
    )
  );
  if($simple_query->have_posts()) :
?>
 
  <ul class="grid">
    <?php while($simple_query->have_posts()) : $simple_query->the_post(); ?><!--
 
   --><li class="grid__item">
        <a href="<?php the_permalink(); ?>">
          <div><?php the_title(); ?></div>
        </a>
      </li><!--
 
 --><?php
      endwhile;
      wp_reset_postdata();
    ?>
  </ul>
 
<?php endif; ?>