Hot Tropica Books
"Hot Tropica Books is a private imprint for a group of writers, editors, and cover artists working in a co-op together and giving back 80% of the net royalties to the authors. This helps them to make writing a career choice and not just a hobby. "
Which seems fine except that I can't say that I know what 'net royalties' are....
"CEO and owner: Michelle Keefe"
"WE ARE CURRENTLY CLOSED FOR SUBMISSIONS UNTIL SPRING 2011."
On their website/blog story lengths are not given. Those 'books' listed on Omnilit seem to be mainly short stories in length.