Author Casia Schreyer has posted an anthology call for an Anthology on Race. She'd like stories of 300 to 10,000 words in any genre that explores the question "What if there was only one race in your country?" The deadline is February 28, 2015 and payment at this point is either a royalty split or perhaps a charity anthology. You can find the details here.
And the first thing I thought about with this call was HG Wells short story "The Country of the Blind", it makes a good jumping off point for ideas.