Yes, while a person is registering for an event they can now upload a document for each attendee. During the setup of the Event on the Event Settings tab scroll down to the Ticketing & Attendees section, after turning on "Capture Attendee Info" a new setting, "Allow Attendee to Upload Document" will appear. Turning on this setting will allow you to customize the public label for the field and what internal category will be attached to the document.
The document will then be uploaded onto that Attendee's Constituent record under their Documents tab. You will also see on the Event Attendance grid a column called, "Document" where you will see a "View" link on each row where a document was uploaded for that Attendee. Clicking the "View" link will take you to that Attendee's document tab within their Constituent record.