Follow these steps if you'd like to collect proof of attendance for DevCon4 and have this proof attached to your decentralised identity.
Sign-up or in to Zinc (https://zinc.work/), your identity (ERC725) is deployed.
Click 'share profile', email your profile link to: firstname.lastname@example.org.
Include a uniquely identifiable piece of information in the email proving your attendance. Such as the colour of Vitalik's t-shirt on Tuesday, the lunch options, or the colour of the hand towels in the bathrooms or a picture of your attendance.
Zinc will then add the claim to your ETH Identity: "Attending DevCon4 2018."
Submit your profile username to this bounty for a payout in ETH.
Demo video: https://medium.com/zinc_work/workshop-attendees-ethberlin-instructions-248414159579
Own a Zinc profile and attend DevCon4