SpeedCrunch - SpeedCrunch. SpeedCrunch is a high-precision scientific calculator featuring a fast, keyboard-driven user interface. It is free and open-source software, licensed under the GPL. Download Documentation Donate .

Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.

Soulver - Soulver is a software application that functions as a calculator that allows you type a continuous stream of information rather than having to input data into multiple cells.

GPG Suite - Use GPG Suite to encrypt, decrypt, sign and verify files or messages.

Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.

GnuPG - GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP).