Not very impressive, I know. The Crypto Tool allows perfoming a couple of cryptographic and mathematic operations on byte arrays.
I made it a long time ago to understand and reproduce cryptographic operations of smart cards (mainly sample calculations in manuals). If you are new to cryptography, this tool may be helpful.
Current version: 126.96.36.199
The Crypto Tool comes without installer. Just download an run it.
If you like the Crypto Tool and find it useful, feel free to donate.