HashCheck Shell Extension - File-integrity verification with CRC-32, MD5, SHA-1, SHA-2 and SHA-3, integrated into Windows...
Batch File Split & Join - Split and merge multiple text or binary files in either character, line, or byte modes. When splitting files, you can split on certain text or binary separator; target given number of parts; or target specific part size. Join files on lines/bytes.
OpenHashTab - OpenHashTab is a shell extension for conveniently calculating and checking file hashes from file properties.
Free File Splitter - File Splitter is a handy freeware program which allows to easily split and merge files
HashMyFiles - HashMyFiles is small utility that allows you to calculate the MD5 and SHA1 hashes of one or more files in your system.
HJSplit - HJSplit is a popular set of freeware file-splitting programs created by Freebyte.