Half it and Half it batch
Many album companies require you to submit single pages, but I like to design in spreads. Half-it lets you automate the process.
Half it
Halt It will split in half an open spread. It will save the halves into the folder where the original is.
Half It Batch
Half It Batch will prompt you to choose a folder. It will then open all Photoshop documents and split them in half for you.
Result
Here you can see an example of split spreads.