Kliu.org HashCheck (http://code.kliu.org/hashcheck/) might be abandoned -- the last site update happened in 2011 -- but as it is a comprehensive solution for its purpose, I believe it deserves mention here at TPFC forums, notably because of its XP compatibility and FOSS release under a BSD license.
Since it is a shell extension, HashCheck is obviously not portable (although installer extraction and silent installation are mentioned in the FAQ page: http://code.kliu.org/hashcheck/faq.html).
http://code.kliu.org/hashcheck/ wrote:The HashCheck Shell Extension makes it easy for anyone to calculate and verify checksums and hashes from Windows Explorer. In addition to integrating file checksumming functionality into Windows, HashCheck can also create and verify SFV files (and other forms of checksum files, such as .md5 files). It is fast and efficient, with a very light disk and memory footprint, and it is open-source.
HashCheck last release (v2.1.11, dated 2009-07-01) can be downloaded from http://code.kliu.org/hashcheck/.
A third party review can be found at http://betanews.com/2017/01/05/easily-highlight-changed-files-with-hashcheck/.
Incidentally, the same author also released hashutils (http://code.kliu.org/misc/hashutils/), a package of freeware CLI hashing tools with folder recursion capability.
Other relevant hashing related topics can be found at:http://code.kliu.org/misc/hashutils/ wrote:These are simple command-line checksumming/hashing utilities for Windows, similar to the ones found on most Unix-like systems. The md5sum and sha1sum utilities found in this package will produce output similar to and compatible with that of their Unix counterparts. md4sum and ed2ksum will produce output similar to that of md5sum, and crc32sum will produce output that is compatible with the SFV file format.