As magical as we are, we can't pull an image of your subscriber out of thin air (nor is Freddie stalking them), but we do know who to ask. For all accounts (paid or free), to display a picture of your subscriber, we use Gravatar to display your subscriber's image. Gravatar is email based and your subscriber has to have one set up.
If you're using MailChimp's socialPro add-on and your recipient has an image, icon or profile picture they use frequently on social networking sites, we will use Twitter first, Facebook 2nd, and Gravatar 3rd.
Why would you want a picture of your subscriber? You might recognize some faces from your list at an event you host and thank them for people a loyal customer. That goes a *LONG* way. Or you might be spending time on twitter and see that your customer is buddies with another friend of yours. We're a visual bunch! It's a good way to remember that your subscribers are people first and email addresses second.