Since SharePoint 2010, it is possible to customize the OOTB display form of a list item, to display the related items, i.e. the items that have a lookup field pointing to this item.
And in the end the customization is very simple: customizing the list (or content type) display form, it is possible to add the related list directly (and not a ListView web part). And it is possible to customize this list too, through a view, to customize columns to display, sorting and filtering (in addition to the filtering given by the connection to the main record).
A complete example showing this process is displayed in the blog post Showing Related List Items in List Display Form Sharepoint 2010.