From Paterva Wiki
This transform queries a public PGP key server to see if the person's name exists in the key database. It returns entries as email address entities. Some things to keep in mind - if the name is very common (John Smith) you are going to get a lot of false positives. Also - the information kept in the database might be out of date. This transform is useful to get long forgotten email addresses for people with an unique name / surname combination.