I am now officially a Certified Scrum Practitioner.
So it signifies that my peers recognize that I understand Scrum pretty well. The certification shows I have actually applied Scrum for real, on a real project, in a real organization, for real stakeholders. It's not a big deal, really. It's just a token from an independent group of people--not me, not my friends, not my coworkers or business partners--that I probably know what I'm doing. But there are only about 1,000 CSPs in the world, so it helps distinguish me from people who haven't been similarly recognized by their peers.
Click through for more information on Scrum, the Scrum Alliance, and the Scrum Alliance certifications.