Similar to the Aspergers thread, but for something that I've struggled with since birth. I thought this would be appropriate since it's the Awareness Week for it aswell.
Before birth, some people's lip or palate (or both, like myself) doesn't form properly, resulting in a cleft. It affects roughly 1 in 700 people in the UK and after birth, the individuals may have various problems like speech deficits or natural hearing loss. These people may also have behaviorial problems later in life. Most people, like myself, live normal lives however.
Wikipedia article on this:
http://en.m.wikipedia.org/wiki/Cleft_lip_and_palate