@Quexos
I tend to agree with jackie_w that your messages are getting annoying.
As for the MD5 checksums, they have been in the Kobo firmware archives for years though they only cover the contents of the upgrade directory.
Personally, I use a program called WinMD5 since it is the easiest to use for a single file and another called FileVerifier++ when I want to generate a text file of the checksums or compare the checksums of existing files to such list. FV++ does offer a choice of multiple checksum/CRC variants which I find useful. Quite a few sites I download from routinely supply the MD5/SHA1/whatever checksums either on the web page or as a separate file so you can test a copy of their file downloaded from another site for corruption or modification.
A quick google search on MD5 will give you more information than most people could want. Even the Wikipedia article is useful though it concentrates more on the vulnerabilities in MD5
http://en.wikipedia.org/wiki/MD5.
Regards,
David