Here are some tools ( for Vista / Seven minimum ) whose goal is to ease the use and understanding of cryptography involved in software and network security.
Some of them may be usefull in the daily life of testers or developpers.

All your comments are welcome :
secret key and password
manual  screenshot
secret key exchange through unsecure network
manual  screenshots
generating public key
manual  screenshots
signing and verifying with public keys
manual  screenshot
a tool to make X509 certificates
manual screenshot
to 'probe' a SSL/TLS server
TLS Cipher Suites
manual  screenshots
SRP Verifiers
SRP Verifiers-EN
manual  screenshots
a multithreaded TLS test server and client TLS Test Pack-EN
manual  screenshots
a multi-transcoder YAED-EN
manual  screenshot
or :
all the tools (dynamically linked) in one package :
Depending of your computer configuration, you may also need the corresponding :
Microsoft C++ runtime components (x86)
  [very] usefull links :
Peter Gutmann's X509 style guide, [homepage],
Key Length
And still about security ... :
last update : wednesday 8 april 2020