Combining two node forms: is that possible? I am using Drupal 6 and I got a node form for a content type. I want to alter the other content type node form inside the first one; is that possible?
You can also use Flexifield to get 2 content types on the same form.

Like docs says: 


  You define a field combination by creating a node type and adding
  fields to it. On a different node type, you can add a flexifield, and
  then on its configuration form, specify which node types to use as
  items within the field.