The Plague* by Linda...In this world about 25% of all males are born hermaphrodites, although they function only as males. A demon creates a plague that kills most of the women of child bearing age, but one of the side effects is that the men who are born hermaphrodites catch the plague and become fully functional as females, without really changing their outward appearance. In order to keep the population from dropping dangerously low the government decides that all the newly functional "breeders" must have a male partner and give birth to at least one child. (Sam/Dean and John/Bobby, a little bit of Dean/John)

Saturday's Child* by Linda Atkinson...Summary not given(John/Dean)

Shadow Lands Updated  by Linda...Bobby Singer and his son Dean are hunters in humankind's war against demons. John Winchester and his son Sam are Shadowen—magical beings who chose to aid humans in the war against the demons. Can these beings from different sides of the supernatural world come together? (John/Bobby, Sam/Dean I toss in some OCs, a few familiar charcters as well)

Tangled by Claudia...Dean finds himself pregnant, after a few hours of sex with his brother. A brother who has just left for college. A brother who doesn't remember those few hours of sex (Sam/Dean)