Jesse Kornblum is a computer forensics author, researcher and engineer.
md5deep and hashdeep - Cross platform recursive hashing and auditing programs, respectively. Computes MD5, SHA-1, SHA-256, Tiger and Whirlpool hashes. Can also match against sets of known hashes. The latter program uses multihashing to conduct a computer forensics audit.
foremost - File carving program
ssdeep - Usually called Fuzzy Hashing, this program implements Context Triggered Piecewise Hashing.
FRED - The First Responder's Evidence Disk
dc3dd - A patch to add forensics features to GNU dd
Miss Identify - Program to identify Win32 executables that don't have an executable extension. Can also identify all executables.