There are many open source tools and utilities for creating and working with checksums for digital newspapers.
Md5sum and sha1sum are standard Unix command-line programs and are usually invoked on a per-file or folder basis. These can be coupled with options and arguments for outputting results to various formats (txt, xml, csv, etc.).
Md5deep/hashdeep are a set of lightweight open source applications that provide technicians with some well defined and user friendly features and commands for creating and working with checksums for digital objects at both file and batch levels.
BagIt is a packaging and transfer specification that can be applied to an existing set of organized collection content. BagIt produces a manifest of per-file checksums and file pathnames (see the Boston College Case Study below for an example of using BagIt for checksum management).