Visual MD5 is a freeware for you to get MD5 checksum of a file. It's a Windows GUI application, which is easy to use and free to distribute. Visual MD5 supports Drag & Drop operation, and can handle multiple files at once.
Full Specifications
What's new in version 1
General
ReleaseNovember 7, 2008
Date AddedSeptember 8, 2006
Version1
Operating Systems
Operating SystemsWindows 2000, Windows Vista, Windows 98, Windows Me, Windows, Windows XP
Additional RequirementsWindows 98/Me/2000/XP/2003 Server/Vista, .NET Framework 1.1/2.0 is required