Conga Contracts - Conga Contracts is management solution designed to accelerate and simplify contract negotiations in Salesforce.
Kleopatra - Kleopatra is a certificate manager and GUI for GnuPG.
Concord - Contract Management Software and unlimited Electronic Signatures. Reduce costs, maximize compliance & mitigate risk. Enterprise solutions available.
GPG Suite - Use GPG Suite to encrypt, decrypt, sign and verify files or messages.
CobbleStone Software - Managing contracts just got easier with CobbleStone!
GnuPG - GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP).