Fish Publishing is the place to go if you write short crime fiction, but especially if you write historical crime. They sponsor several contests over the summer, with the winners receiving cash and publication in an anthology. They have the Micro-Fiction Showcase (deadline Aug 31),  Fish-Knife Award (deadline Sept 30), Short Histories III (deadline Sept 30), Criminally-Short Short Histories (deadline Sept 30), and the 14th Fish International Short Story Prize (deadline Nov 30). All of these contests are online submissions only, with story lengths and prizes of varying size.