I heard you like switches

better.php

<?php

function my_module_nodeapi(&$node, $op, $teaser, $page){
  $func = 'my_module_nodeapi_'.$node->type.'_'.$op;
  if(function_exists($func)){
    $func(&$node, $teaser, $page);
  }
}

switches_so_many_switches.php

<?php
function my_module_nodeapi(&$node, $op, $teaser, $page) {

  switch ($op) {
    case 'view':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'load':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'insert':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'update':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'delete':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'load':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
    case 'presave':
      switch ($node->type) {
        case 'my_node_type':
          //do the things
          break;
        case 'my_second_node_type':
          //do the things
          break;
      }
      break;
  }
}