Long story short, I needed quick utilities to calculate MD5 and SHA-1 hashes for file input. Once I finished those I decided to extend the toolkit to use MD5, SHA-1/-256/-384/-512, and RIPEMD-160 out of sheer boredom. I've also tested them against hashes generated by OpenSSL; they work.
You can grab the version 1.0 binaries here
and the GPLed C# source here
The tools are written using the .NET Framework 2.0. Vista has this preinstalled. If you're on an earlier operating system and don't already have it installed, you can grab the installer from the Microsoft Download Center
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