WinMd5Sum (portable)

WinMd5Sum Portable is a simple MD5 sum checker that allows you to check and compare the md5 sums of files. 

What's an MD5 Sum? An MD5 sum is a cryptographic hash used to verify the integrity of files. So, when you download a file, you can check what the publisher says the MD5 sum is and compare it to the MD5 sum of the file you have.

http://portableapps.com/apps/utilities/winmd5sum_portable

More about MD5...

CCleaner x86 & x64 (portable)

CCleaner portable is the number-one tool for cleaning your Windows PC. It protects your privacy online and makes your computer faster and more secure. Easy to use and a small, fast download.

CCleaner is a small, effective utility for computers running Microsoft Windows that cleans out the 'junk' that accumulates over time: temporary files, broken shortcuts, and other problems.
CCleaner protects your privacy. It cleans your browsing history and temporary internet files. Allowing you to be a more confident Internet user and less susceptible to identity theft.

http://www.piriform.com/ccleaner/download/portable

PeerBlock x86 & x64 (portable)

PeerBlock is an IP firewall with support for blacklists and whitelists. It can be used to block advertising, spyware, activity monitoring and more. PeerBlock requires admin rights to function.

PeerBlock Portable includes the 32-bit and 64-bit variants of both the legacy and modern versions of PeerBlock, automatically selecting the appropriate one, for full support on every PC you use.


x86 & x64  https://portableapps.com/apps/security/peerblock-portable