If you want to use your computer to make a book or a magazine, the final step before printing is called imposition. Cheap Impostor is a simple yet powerful alternative to fancy imposition software. It doesn't offer all the features of high-end imposition software (which costs hundreds or thousands of dollars). Hence the name.
However, if you want to print and bind booklets, magazines, or even long books, this program might be all the imposition software you need.
Let's say you want to make a magazine from a document you've written. You would like to have the magazine be the size of a sheet of paper folded in half. Without imposition software the simplest way to transform your document into a magazine would be to use a photo-copier to shrink and re-order the pages so two fit sideways on a sheet of paper, and so that when a stack of them is stapled and folded in half the pages appear in the correct order.
The short story is that Cheap Impostor lets you skip the photocopier step, and produce output from your printer that can directly be turned into a magazine. Further, Cheap Impostor has settings that let you create books with multiple signatures.