KSig is a graphical tool for keeping track of many different email signatures. The signatures themselves can be edited through KSig's graphical user interface. A command-line interface is then available for generating random or daily signatures from a list. The command-line interface makes a suitable plugin for generating signatures in external mail clients such as KMail or any other client that can obtain the signature text from the output of a command.
Random signatures will pull signatures from the KSig signature file randomly. You can make every email more exiciting and unique than the previous by creating multiple signatures with varying quotes, styles, and information.
Daily signatures will pull signatures from the KSig signature file only using one signature for an entire day. Every day will provide a different signature, and just like the random signatures provide uniqueness to your emails.
Please report any problems or feature requests to the KDE mailing lists.