If you are a YC founder, your username will show up in orange to other YC founders to enable these entrepreneurs to recognize and meet each other.
I've been aware of this for a while (a few YC founders I got to meet confided this to me), but it is the first time I've seen it being publicly admitted.
Along with the DMCA[1] link below, I'm happy to see this ever increasing level of transparency on Hacker News. I believe it is a great way to foster trust among the community.