Creating contacts and/or companies in workflows

For salespeople it would come handy if they could create a contact via a workflow. While being on the phone with a prospect, they might have created a deal already but dont know the full information on the contact that the deal is related to. So what would be nice is if we could create that contact via worklow without mail and assign it automatically to that deal. Even if the assigning would be manual, it would be way easier if the contact would have been created before..