I have made some 'breast pockets' for Melanie Testa. She is aiming to collect 1000 breast pockets in support of woman with breast cancer who choose not to have reconstructive surgery after a mastectomy. You can read more about it here.
I don't know any 'flatties' but have a friend who has had a lot of problems with her reconstructive surgery. I have always thought that if I was in the same situation I would go 'flat'.
These were fun to make - playing with commercial and dyed fabrics and adding a little bit of hand stitching.