How to change the email alias for the workflow email notifications/reminders? Instead of recieving emails with title 'firstname.lastname@example.org', to be 'Nintex Services'.
Out of the blue ... if you're using for e.g. Exchange you would need to create at least some kind of address-book entry with this mail-address. The easiest way to accomplish this would be to create a user with this address. This way clients (like outlook) would show the realname based on the addressbook-entry instead of the mail-address.
This is just a random thought - I haven't tried this though.