Reddit's having some incest threads. Here's a collection of links.
"I had sex with my brother but I don't feel guilty"
"I am in love with my sister, and she reciprocates"
"I lost my virginity to my sister."
Hapsburg Family Tree
"Brothers and Sisters in Love" (with photos)
"Forbidden Love Between Siblings" (couple wants to move to france where incest is legal)
"Brother, sister lose legal incest attempt" (they have 4 kids together, court keeps throwing brother in jail for it)